diff --git a/git-svnimport.perl b/git-svnimport.perl
index 4ae0eecd37..f6eff8e32a 100755
--- a/git-svnimport.perl
+++ b/git-svnimport.perl
@@ -853,7 +853,7 @@ sub commit {
 		print $out ("object $cid\n".
 		    "type commit\n".
 		    "tag $dest\n".
-		    "tagger $committer_name <$committer_email>\n") and
+		    "tagger $committer_name <$committer_email> 0 +0000\n") and
 		close($out)
 		    or die "Cannot create tag object $dest: $!\n";
 
diff --git a/sha1_file.c b/sha1_file.c
index 1a246f5f93..25c0bf9134 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -671,14 +671,8 @@ static void reprepare_packed_git(void)
 
 int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
 {
-	char header[100];
 	unsigned char real_sha1[20];
-	SHA_CTX c;
-
-	SHA1_Init(&c);
-	SHA1_Update(&c, header, 1+sprintf(header, "%s %lu", type, size));
-	SHA1_Update(&c, map, size);
-	SHA1_Final(real_sha1, &c);
+	hash_sha1_file(map, size, type, real_sha1);
 	return hashcmp(sha1, real_sha1) ? -1 : 0;
 }
 
@@ -1364,9 +1358,9 @@ void *read_object_with_reference(const unsigned char *sha1,
 	}
 }
 
-static char *write_sha1_file_prepare(void *buf, unsigned long len,
-                                     const char *type, unsigned char *sha1,
-                                     unsigned char *hdr, int *hdrlen)
+static void write_sha1_file_prepare(void *buf, unsigned long len,
+                                    const char *type, unsigned char *sha1,
+                                    unsigned char *hdr, int *hdrlen)
 {
 	SHA_CTX c;
 
@@ -1378,8 +1372,6 @@ static char *write_sha1_file_prepare(void *buf, unsigned long len,
 	SHA1_Update(&c, hdr, *hdrlen);
 	SHA1_Update(&c, buf, len);
 	SHA1_Final(sha1, &c);
-
-	return sha1_file_name(sha1);
 }
 
 /*
@@ -1538,7 +1530,8 @@ int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned cha
 	/* Normally if we have it in the pack then we do not bother writing
 	 * it out into .git/objects/??/?{38} file.
 	 */
-	filename = write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
+	write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
+	filename = sha1_file_name(sha1);
 	if (returnsha1)
 		hashcpy(returnsha1, sha1);
 	if (has_sha1_file(sha1))