diff --git a/PBGitCommit.m b/PBGitCommit.m
index 3944e4f..0abc3f0 100644
--- a/PBGitCommit.m
+++ b/PBGitCommit.m
@@ -22,9 +22,11 @@
 	NSMutableArray *p = [NSMutableArray arrayWithCapacity:nParents];
 	for (i = 0; i < nParents; ++i)
 	{
-		char *s = git_oid_mkhex(parentShas + i);
+		char s[41];
+		git_oid_fmt(s, parentShas + i);
+		s[40] = 0;
 		[p addObject:[NSString stringWithUTF8String:s]];
-		free(s);
+//		free(s);
 	}
 	return p;
 }
@@ -121,9 +123,12 @@
 
 - (NSString *)realSha
 {
-	char *hex = git_oid_mkhex(&sha);
+	char hex[41];
+	git_oid_fmt(hex, &sha);
+	hex[40] = 0;
+//	char *hex = git_oid_mkhex(&sha);
 	NSString *str = [NSString stringWithUTF8String:hex];
-	free(hex);
+//	free(hex);
 	return str;
 }