diff --git a/CBFlib/src/fcb_skip_whitespace.f90 b/CBFlib/src/fcb_skip_whitespace.f90
index e60ad17..8b97887 100644
--- a/CBFlib/src/fcb_skip_whitespace.f90
+++ b/CBFlib/src/fcb_skip_whitespace.f90
@@ -65,11 +65,11 @@
 		     END IF
 		  ELSE
 		     SELECT CASE (LINE(IC))
-		     CASE (Z'5C')      ! backslash
+		     CASE (INT(Z'5C'))      ! backslash
 			IC = IC+1      ! force skip of next character
-		     CASE (Z'28')      ! open paren
+		     CASE (INT(Z'28'))      ! open paren
 			COMMENT_LEVEL = COMMENT_LEVEL+1;
-		     CASE (Z'29')      ! close paren
+		     CASE (INT(Z'29'))      ! close paren
 			COMMENT_LEVEL = COMMENT_LEVEL-1;
 		     END SELECT
 		     IC = IC+1;