diff --git a/CHANGELOG.txt b/CHANGELOG.txt
index 8a694350..299addc6 100644
--- a/CHANGELOG.txt
+++ b/CHANGELOG.txt
@@ -4,6 +4,7 @@
 
 == ruote - 2.2.1    not yet released
 
+- fix for :if => '${a}' when a like '456ab' (Thanks John Le)
 - StorageParticipant :count => true uniformization (Thanks Jan Topiński)
 - StorageParticipant#by_fei (alias for #[])
 
diff --git a/lib/ruote/exp/condition.rb b/lib/ruote/exp/condition.rb
index 340ce2a2..7c7140e5 100644
--- a/lib/ruote/exp/condition.rb
+++ b/lib/ruote/exp/condition.rb
@@ -103,7 +103,11 @@ def self.parse(conditional)
         "/!\\ please upgrade your rufus-treechecker gem /!\\"
       )
 
-    rescue => e
+    rescue SyntaxError => se
+
+      [ :str, conditional ]
+
+    rescue Exception => e
 
       [ :false ]
     end
diff --git a/test/functional/ft_10_dollar.rb b/test/functional/ft_10_dollar.rb
index d5174c10..6d25695f 100644
--- a/test/functional/ft_10_dollar.rb
+++ b/test/functional/ft_10_dollar.rb
@@ -264,5 +264,25 @@ def test_literally_and_participant_params
       { 'b' => %w[ A B C ], 'ref' => 'alpha' },
       r['workitem']['fields']['parameters'])
   end
+
+  # Issue pointed out by John Le.
+  #
+  def test_not_a_number
+
+    pdef = Ruote.define do
+      echo 'a0', :if => '${a}'
+      echo 'a1', :if => '${a} is set'
+      echo 'b', :if => '${b}'
+      echo 'c'
+    end
+
+    wfid = @engine.launch(
+      pdef,
+      'a' => '0a')
+
+    @engine.wait_for(wfid)
+
+    assert_equal "a0\na1\nc", @tracer.to_s
+  end
 end