diff --git a/mutt-1.5.21-certscomp.patch b/mutt-1.5.21-certscomp.patch
index 5935098..7fe2ef6 100644
--- a/mutt-1.5.21-certscomp.patch
+++ b/mutt-1.5.21-certscomp.patch
@@ -7,7 +7,7 @@ diff -up mutt-1.5.21/mutt_ssl_gnutls.c.debug mutt-1.5.21/mutt_ssl_gnutls.c
  
 -    ptr = (unsigned char *)strstr((char*)b64_data.data, CERT_SEP) + 1;
 -    ptr = (unsigned char *)strstr((char*)ptr, CERT_SEP);
-+    ptr = (unsigned char *)memmem((char*)b64_data.data, b64_data.size, CERT_SEP, sizeof(CERT_SEP));
++    ptr = (unsigned char *)memmem((char*)b64_data.data, b64_data.size, CERT_SEP, sizeof(CERT_SEP-1));
 +    if (ptr == NULL)
 +    {
 +      gnutls_free(cert.data);
@@ -16,6 +16,6 @@ diff -up mutt-1.5.21/mutt_ssl_gnutls.c.debug mutt-1.5.21/mutt_ssl_gnutls.c
 +    }
  
 +    ptr += 1;
-+    ptr = (unsigned char *)memmem((char*)ptr, b64_data.size - (ptr - b64_data.data), CERT_SEP, sizeof(CERT_SEP));
++    ptr = (unsigned char *)memmem((char*)ptr, b64_data.size - (ptr - b64_data.data), CERT_SEP, sizeof(CERT_SEP-1));
      b64_data.size = b64_data.size - (ptr - b64_data.data);
      b64_data.data = ptr;
diff --git a/mutt.spec b/mutt.spec
index 938e972..a9fc8ba 100644
--- a/mutt.spec
+++ b/mutt.spec
@@ -16,7 +16,7 @@
 Summary: A text mode mail user agent
 Name: mutt
 Version: 1.5.21
-Release: 19%{?dist}
+Release: 20%{?dist}
 Epoch: 5
 # The entire source code is GPLv2+ except
 # pgpewrap.c setenv.c sha1.c wcwidth.c which are Public Domain
@@ -177,6 +177,10 @@ ln -sf ./muttrc.5 $RPM_BUILD_ROOT%{_mandir}/man5/muttrc.local.5
 %{_mandir}/man5/muttrc.*
 
 %changelog
+* Wed May 29 2013 Honza Horak <hhorak@redhat.com> - 5:1.5.21-20
+- Fix patch for #750929
+  Resolves: #957542
+
 * Mon May 20 2013 Honza Horak <hhorak@redhat.com> - 5:1.5.21-19
 - Fix missing options in doc and pgpring, pgpewrap man page