diff --git a/java/compiler/impl/src/com/intellij/packaging/impl/elements/ManifestFileUtil.java b/java/compiler/impl/src/com/intellij/packaging/impl/elements/ManifestFileUtil.java
index 2aa991e0b1fa..4aeda0815f8e 100644
--- a/java/compiler/impl/src/com/intellij/packaging/impl/elements/ManifestFileUtil.java
+++ b/java/compiler/impl/src/com/intellij/packaging/impl/elements/ManifestFileUtil.java
@@ -34,6 +34,7 @@ import com.intellij.openapi.roots.OrderEnumerator;
 import com.intellij.openapi.roots.ProjectRootManager;
 import com.intellij.openapi.ui.Messages;
 import com.intellij.openapi.ui.TextFieldWithBrowseButton;
+import com.intellij.openapi.util.Computable;
 import com.intellij.openapi.util.Ref;
 import com.intellij.openapi.util.io.FileUtil;
 import com.intellij.openapi.util.text.StringUtil;
@@ -348,8 +349,13 @@ public class ManifestFileUtil {
   }
 
   private static class MainClassFilter implements ClassFilter {
-    public boolean isAccepted(PsiClass aClass) {
-      return PsiMethodUtil.MAIN_CLASS.value(aClass) && PsiMethodUtil.hasMainMethod(aClass);
+    public boolean isAccepted(final PsiClass aClass) {
+      return ApplicationManager.getApplication().runReadAction(new Computable<Boolean>() {
+        @Override
+        public Boolean compute() {
+          return PsiMethodUtil.MAIN_CLASS.value(aClass) && PsiMethodUtil.hasMainMethod(aClass);
+        }
+      });
     }
   }
 }