diff --git a/ChangeLog b/ChangeLog
index b1bfa5c98..09bb79074 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -57,6 +57,7 @@ Bugs
  + Fixed bug #1065, where CmdShow issued messages in incorrect situations.
  + Partially fixed #1083, which showed 'task 0 ...' when modifying a non-
    pending task (thanks to Aikido Guy).
+ + Fixed bug #1091, allowing filters to use 'urgency.over:4.5'.
  + Fixed bug #1110, which did not treat 'status:Completed' the same
    as 'status:completed' (thanks to Aikido Guy).
  + Fixed bug #1123, which caused the undo of a 'log' command to corrupt the data
diff --git a/src/A3.cpp b/src/A3.cpp
index 4a7175df0..7c8df9d89 100644
--- a/src/A3.cpp
+++ b/src/A3.cpp
@@ -97,7 +97,7 @@ static struct
   {  "_hastag_", 9,         'b',  0,      'l'},     // +tag  [Pseudo-op]
   {  "_notag_",  9,         'b',  0,      'l'},     // -tag  [Pseudo-op]
 
-//  {  "-",       15,         'u',  1,      'r' },    // Unary minus
+  {  "-",       15,         'u',  1,      'r' },    // Unary minus
   {  "*",       13,         'b',  1,      'l' },    // Multiplication
   {  "/",       13,         'b',  1,      'l' },    // Division
 //  {  "%",       13,         'b',  1,      'l' },    // Modulus
diff --git a/src/E9.cpp b/src/E9.cpp
index 4d19a5b17..241b51be5 100644
--- a/src/E9.cpp
+++ b/src/E9.cpp
@@ -337,6 +337,32 @@ void E9::operator_lt (Arg& result, Arg& left, Arg& right)
                     : "false";
     }
   }
+  else if (left._type  == Arg::type_duration ||
+           right._type == Arg::type_duration)
+  {
+    if (left._value == "" ||
+        right._value == "")
+      result._value = "false";
+    else
+    {
+      Duration left_duration  (left._value);
+      Duration right_duration (right._value);
+
+      result._value = (left_duration < right_duration)
+                    ? "true"
+                    : "false";
+    }
+  }
+  else if (left._type  == Arg::type_number ||
+           right._type == Arg::type_number)
+  {
+    float left_number  = strtof (left._value.c_str (), NULL);
+    float right_number = strtof (right._value.c_str (), NULL);
+
+    result._value = (left_number < right_number)
+                  ? "true"
+                  : "false";
+  }
   else
   {
     result._value = (left._value < right._value)
@@ -376,6 +402,32 @@ void E9::operator_lte (Arg& result, Arg& left, Arg& right)
                     : "false";
     }
   }
+  else if (left._type  == Arg::type_duration ||
+           right._type == Arg::type_duration)
+  {
+    if (left._value == "" ||
+        right._value == "")
+      result._value = "false";
+    else
+    {
+      Duration left_duration  (left._value);
+      Duration right_duration (right._value);
+
+      result._value = (left_duration <= right_duration)
+                    ? "true"
+                    : "false";
+    }
+  }
+  else if (left._type  == Arg::type_number ||
+           right._type == Arg::type_number)
+  {
+    float left_number  = strtof (left._value.c_str (), NULL);
+    float right_number = strtof (right._value.c_str (), NULL);
+
+    result._value = (left_number <= right_number)
+                  ? "true"
+                  : "false";
+  }
   else
   {
     result._value = (left._value <= right._value)
@@ -415,6 +467,32 @@ void E9::operator_gte (Arg& result, Arg& left, Arg& right)
                     : "false";
     }
   }
+  else if (left._type  == Arg::type_duration ||
+           right._type == Arg::type_duration)
+  {
+    if (left._value == "" ||
+        right._value == "")
+      result._value = "false";
+    else
+    {
+      Duration left_duration  (left._value);
+      Duration right_duration (right._value);
+
+      result._value = (left_duration >= right_duration)
+                    ? "true"
+                    : "false";
+    }
+  }
+  else if (left._type  == Arg::type_number ||
+           right._type == Arg::type_number)
+  {
+    float left_number  = strtof (left._value.c_str (), NULL);
+    float right_number = strtof (right._value.c_str (), NULL);
+
+    result._value = (left_number >= right_number)
+                  ? "true"
+                  : "false";
+  }
   else
   {
     result._value = (left._value >= right._value)
@@ -453,6 +531,32 @@ void E9::operator_gt (Arg& result, Arg& left, Arg& right)
                                     : "false";
     }
   }
+  else if (left._type  == Arg::type_duration ||
+           right._type == Arg::type_duration)
+  {
+    if (left._value == "" ||
+        right._value == "")
+      result._value = "false";
+    else
+    {
+      Duration left_duration  (left._value);
+      Duration right_duration (right._value);
+
+      result._value = result._value = (left_duration > right_duration)
+                                    ? "true"
+                                    : "false";
+    }
+  }
+  else if (left._type  == Arg::type_number ||
+           right._type == Arg::type_number)
+  {
+    float left_number  = strtof (left._value.c_str (), NULL);
+    float right_number = strtof (right._value.c_str (), NULL);
+
+    result._value = (left_number > right_number)
+                  ? "true"
+                  : "false";
+  }
   else
   {
     result._value = (left._value > right._value)
diff --git a/test/op_gt.t b/test/op_gt.t
index e231828f9..3133b5e5c 100755
--- a/test/op_gt.t
+++ b/test/op_gt.t
@@ -28,7 +28,7 @@
 
 use strict;
 use warnings;
-use Test::More tests => 22;
+use Test::More tests => 26;
 
 # Create the rc file.
 if (open my $fh, '>', 'op.rc')
@@ -76,6 +76,12 @@ like   ($output, qr/two/,   'ls description > t --> two');
 like   ($output, qr/three/, 'ls description > t --> three');
 unlike ($output, qr/four/,  'ls description > t --> !four');
 
+$output = qx{../src/task rc:op.rc 'urgency > 10.0' ls 2>&1};
+like   ($output, qr/one/,   'ls urgency > 10 --> one');
+like   ($output, qr/two/,   'ls urgency > 10 --> two');
+unlike ($output, qr/three/, 'ls urgency > 10 --> !three');
+unlike ($output, qr/four/,  'ls urgency > 10 --> !four');
+
 # Cleanup.
 unlink qw(pending.data completed.data undo.data backlog.data synch.key op.rc);
 ok (! -r 'pending.data'   &&
diff --git a/test/op_gte.t b/test/op_gte.t
index 6eb84b3c4..03375331f 100755
--- a/test/op_gte.t
+++ b/test/op_gte.t
@@ -28,7 +28,7 @@
 
 use strict;
 use warnings;
-use Test::More tests => 10;
+use Test::More tests => 14;
 
 # Create the rc file.
 if (open my $fh, '>', 'op.rc')
@@ -58,6 +58,12 @@ like   ($output, qr/two/,   'ls description >= t --> two');
 like   ($output, qr/three/, 'ls description >= t --> three');
 unlike ($output, qr/four/,  'ls description >= t --> !four');
 
+$output = qx{../src/task rc:op.rc 'urgency >= 2.0' ls 2>&1};
+like   ($output, qr/one/,   'ls urgency >= 2.0 --> one');
+like   ($output, qr/two/,   'ls urgency >= 2.0 --> two');
+unlike ($output, qr/three/, 'ls urgency >= 2.0 --> !three');
+unlike ($output, qr/four/,  'ls urgency >= 2.0 --> !four');
+
 # Cleanup.
 unlink qw(pending.data completed.data undo.data backlog.data synch.key op.rc);
 ok (! -r 'pending.data'   &&
diff --git a/test/op_lt.t b/test/op_lt.t
index 1760ce9d5..8c51271fa 100755
--- a/test/op_lt.t
+++ b/test/op_lt.t
@@ -28,7 +28,7 @@
 
 use strict;
 use warnings;
-use Test::More tests => 22;
+use Test::More tests => 26;
 
 # Create the rc file.
 if (open my $fh, '>', 'op.rc')
@@ -76,6 +76,12 @@ unlike ($output, qr/two/,   'ls description < t --> !two');
 unlike ($output, qr/three/, 'ls description < t --> !three');
 like   ($output, qr/four/,  'ls description < t --> four');
 
+$output = qx{../src/task rc:op.rc 'urgency < 10.0' ls 2>&1};
+unlike ($output, qr/one/,   'ls description < 10 --> !one');
+unlike ($output, qr/two/,   'ls description < 10 --> !two');
+like   ($output, qr/three/, 'ls description < 10 --> three');
+like   ($output, qr/four/,  'ls description < 10 --> four');
+
 # Cleanup.
 unlink qw(pending.data completed.data undo.data backlog.data synch.key op.rc);
 ok (! -r 'pending.data'   &&
diff --git a/test/op_lte.t b/test/op_lte.t
index e6f214bb1..678771edd 100755
--- a/test/op_lte.t
+++ b/test/op_lte.t
@@ -28,7 +28,7 @@
 
 use strict;
 use warnings;
-use Test::More tests => 10;
+use Test::More tests => 14;
 
 # Create the rc file.
 if (open my $fh, '>', 'op.rc')
@@ -58,6 +58,12 @@ unlike ($output, qr/two/,   'ls description <= t --> !two');
 unlike ($output, qr/three/, 'ls description <= t --> !three');
 like   ($output, qr/four/,  'ls description <= t --> four');
 
+$output = qx{../src/task rc:op.rc 'urgency <= 2.0' ls 2>&1};
+unlike ($output, qr/one/,   'ls urgency <= 2.0 --> !one');
+unlike ($output, qr/two/,   'ls urgency <= 2.0 --> !two');
+like   ($output, qr/three/, 'ls urgency <= 2.0 --> three');
+like   ($output, qr/four/,  'ls urgency <= 2.0 --> four');
+
 # Cleanup.
 unlink qw(pending.data completed.data undo.data backlog.data synch.key op.rc);
 ok (! -r 'pending.data'   &&