diff --git a/prism/include/PrismMTBDD.h b/prism/include/PrismMTBDD.h
index 94e39ef9..5de04d58 100644
--- a/prism/include/PrismMTBDD.h
+++ b/prism/include/PrismMTBDD.h
@@ -50,10 +50,10 @@ JNIEXPORT jstring JNICALL Java_mtbdd_PrismMTBDD_PM_1GetErrorMessage
 /*
  * Class:     mtbdd_PrismMTBDD
  * Method:    PM_Reachability
- * Signature: (JJIJIJLprism/Prism;)J
+ * Signature: (JJIJIJ)J
  */
 JNIEXPORT jlong JNICALL Java_mtbdd_PrismMTBDD_PM_1Reachability
-  (JNIEnv *, jclass, jlong, jlong, jint, jlong, jint, jlong, jobject);
+  (JNIEnv *, jclass, jlong, jlong, jint, jlong, jint, jlong);
 
 /*
  * Class:     mtbdd_PrismMTBDD
diff --git a/prism/src/mtbdd/PM_Reachability.cc b/prism/src/mtbdd/PM_Reachability.cc
index 6bc5e27d..ae4e8d91 100644
--- a/prism/src/mtbdd/PM_Reachability.cc
+++ b/prism/src/mtbdd/PM_Reachability.cc
@@ -46,8 +46,8 @@ jlong __jlongpointer rv,	// row vars
 jint num_rvars,
 jlong __jlongpointer cv,	// col vars
 jint num_cvars,
-jlong __jlongpointer s,	// start state
-jobject prism)
+jlong __jlongpointer s	// start state
+)
 {
 	DdNode *trans01 = jlong_to_DdNode(t01);		// 0-1 trans matrix
 	DdNode *init = jlong_to_DdNode(s);		// start state