Index: trunk/psModules/src/imcombine/pmSubtractionKernels.h
===================================================================
--- trunk/psModules/src/imcombine/pmSubtractionKernels.h	(revision 26156)
+++ trunk/psModules/src/imcombine/pmSubtractionKernels.h	(revision 26157)
@@ -52,5 +52,5 @@
     PS_ASSERT_PTR_NON_NULL(KERNELS, RETURNVALUE); \
     PS_ASSERT_STRING_NON_EMPTY((KERNELS)->description, RETURNVALUE); \
-    PS_ASSERT_INT_POSITIVE((KERNELS)->num, RETURNVALUE); \
+    PS_ASSERT_INT_NONNEGATIVE((KERNELS)->num, RETURNVALUE); \
     PS_ASSERT_VECTOR_NON_NULL((KERNELS)->u, RETURNVALUE); \
     PS_ASSERT_VECTOR_NON_NULL((KERNELS)->v, RETURNVALUE); \