diff --git a/ruta-ep-ide-ui/src/main/java/org/apache/uima/ruta/ide/validator/LanguageCheckerVisitor.java b/ruta-ep-ide-ui/src/main/java/org/apache/uima/ruta/ide/validator/LanguageCheckerVisitor.java
index caa3281..0bfec22 100644
--- a/ruta-ep-ide-ui/src/main/java/org/apache/uima/ruta/ide/validator/LanguageCheckerVisitor.java
+++ b/ruta-ep-ide-ui/src/main/java/org/apache/uima/ruta/ide/validator/LanguageCheckerVisitor.java
@@ -774,7 +774,7 @@
       List<String> asList = Arrays.asList(keywords);
       if (!StringUtils.isEmpty(conditionName) && !"-".equals(conditionName)
               && !asList.contains(conditionName) && !implicitString.equals(cond.getName())
-              && !conditionExtensions.keySet().contains(cond)) {
+              && !conditionExtensions.keySet().contains(conditionName)) {
         IProblem problem = problemFactory.createUnknownConditionProblem(cond);
         pr.reportProblem(problem);
       }