diff --git a/zlib-1.2.7-optimized-s390.patch b/zlib-1.2.7-optimized-s390.patch
new file mode 100644
index 0000000..b8a158c
--- /dev/null
+++ b/zlib-1.2.7-optimized-s390.patch
@@ -0,0 +1,48 @@
+diff -upr zlib-1.2.7.orig/deflate.c zlib-1.2.7/deflate.c
+--- zlib-1.2.7.orig/deflate.c	2012-02-13 01:15:47.000000000 +0100
++++ zlib-1.2.7/deflate.c	2012-08-13 12:58:49.275911722 +0200
+@@ -1143,15 +1143,16 @@ local void lm_init (s)
+ /* For 80x86 and 680x0, an optimized version will be provided in match.asm or
+  * match.S. The code will be functionally equivalent.
+  */
+-local uInt longest_match(s, cur_match)
++local uInt longest_match(s, pcur_match)
+     deflate_state *s;
+-    IPos cur_match;                             /* current match */
++    IPos pcur_match;                             /* current match */
+ {
++    uLong cur_match = pcur_match; /* extend to pointer width */
+     unsigned chain_length = s->max_chain_length;/* max hash chain length */
+     register Bytef *scan = s->window + s->strstart; /* current string */
+     register Bytef *match;                       /* matched string */
+     register int len;                           /* length of current match */
+-    int best_len = s->prev_length;              /* best match length so far */
++    uLong best_len = s->prev_length;              /* best match length so far */
+     int nice_match = s->nice_match;             /* stop if match long enough */
+     IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
+         s->strstart - (IPos)MAX_DIST(s) : NIL;
+@@ -1159,19 +1160,19 @@ local uInt longest_match(s, cur_match)
+      * we prevent matches with the string of window index 0.
+      */
+     Posf *prev = s->prev;
+-    uInt wmask = s->w_mask;
++    uLong wmask = s->w_mask;
+ 
+ #ifdef UNALIGNED_OK
+     /* Compare two bytes at a time. Note: this is not always beneficial.
+      * Try with and without -DUNALIGNED_OK to check.
+      */
+     register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
+-    register ush scan_start = *(ushf*)scan;
+-    register ush scan_end   = *(ushf*)(scan+best_len-1);
++    register uInt scan_start = *(ushf*)scan;
++    register uInt scan_end   = *(ushf*)(scan+best_len-1);
+ #else
+     register Bytef *strend = s->window + s->strstart + MAX_MATCH;
+-    register Byte scan_end1  = scan[best_len-1];
+-    register Byte scan_end   = scan[best_len];
++    register uInt scan_end1  = scan[best_len-1];
++    register uInt scan_end   = scan[best_len];
+ #endif
+ 
+     /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
diff --git a/zlib.spec b/zlib.spec
index 1d6d23e..27d342c 100644
--- a/zlib.spec
+++ b/zlib.spec
@@ -1,10 +1,11 @@
 Summary: The zlib compression and decompression library
 Name: zlib
 Version: 1.2.7
-Release: 5%{?dist}
+Release: 6%{?dist}
 Group: System Environment/Libraries
 Source: http://www.zlib.net/zlib-%{version}.tar.bz2
 Patch0: zlib-1.2.5-minizip-fixuncrypt.patch
+Patch1: zlib-1.2.7-optimized-s390.patch
 URL: http://www.zlib.net/
 # /contrib/dotzlib/ have Boost license
 License: zlib and Boost
@@ -56,6 +57,9 @@ developing applications which use minizip.
 %prep
 %setup -q
 %patch0 -p1 -b .fixuncrypt
+%ifarch s390 s390x
+%patch1 -p1 -b .optimized-deflate
+%endif
 iconv -f windows-1252 -t utf-8 <ChangeLog >ChangeLog.tmp
 mv ChangeLog.tmp ChangeLog
 
@@ -121,6 +125,9 @@ rm -f $RPM_BUILD_ROOT%{_libdir}/*.la
 %{_libdir}/pkgconfig/minizip.pc
 
 %changelog
+* Mon Aug 13 2012 Peter Schiffer <pschiffe@redhat.com> - 1.2.7-6
+- added patch from IBM which optimizes deflate on s390(x) architectures
+
 * Thu Aug 02 2012 Peter Schiffer <pschiffe@redhat.com> - 1.2.7-5
 - resolves: #832545
   recompiled with -fPIC flag