Index: atomic/os390/atomic.c
===================================================================
--- atomic/os390/atomic.c	(revision 583255)
+++ atomic/os390/atomic.c	(working copy)
@@ -82,6 +82,30 @@
     return old; /* old is automatically updated from mem on cs failure */
 }
 
+#if APR_SIZEOF_VOIDP == 4
+void *apr_atomic_casptr(volatile void **mem_ptr,
+                        void *swap_ptr,
+                        const void *cmp_ptr )
+{
+     __cs1 (&cmp_ptr,    /* automatically updated from mem on __cds1 failure */
+            mem_ptr,     /* set from swap when __cds1 succeeds               */
+            &swap_ptr);
+     return (void *)cmp_ptr;
+}
+#elif APR_SIZEOF_VOIDP == 8
+void *apr_atomic_casptr(volatile void **mem_ptr,
+                        void *swap_ptr,
+                        const void *cmp_ptr )
+{
+     __csg (&cmp_ptr,    /* automatically updated from mem on __cds1 failure */
+            mem_ptr,     /* set from swap when __csg succeeds                */
+            &swap_ptr);  
+     return (void *)cmp_ptr;
+}
+#else
+#error APR_SIZEOF_VOIDP value not supported
+#endif /* APR_SIZEOF_VOIDP */
+
 apr_uint32_t apr_atomic_xchg32(volatile apr_uint32_t *mem, apr_uint32_t val)
 {
     apr_uint32_t old, new_val;