diff --git a/src/main/org/apache/tools/ant/taskdefs/optional/sitraka/CovBase.java b/src/main/org/apache/tools/ant/taskdefs/optional/sitraka/CovBase.java
index a7f21f176..b93e56a26 100644
--- a/src/main/org/apache/tools/ant/taskdefs/optional/sitraka/CovBase.java
+++ b/src/main/org/apache/tools/ant/taskdefs/optional/sitraka/CovBase.java
@@ -127,7 +127,7 @@ public abstract class CovBase extends Task {
     }
 
     protected String getParamFileArgument() {
-        return (!isJProbe4 ? "-jp_" : "") + "paramfile=";
+        return "-" + (!isJProbe4 ? "jp_" : "") + "paramfile=";
     }
 
     /**