diff --git a/doc/src/sgml/installation.sgml b/doc/src/sgml/installation.sgml
index e0bea34fd8..71d5fb1e03 100644
--- a/doc/src/sgml/installation.sgml
+++ b/doc/src/sgml/installation.sgml
@@ -1,4 +1,4 @@
-<!-- $Header: /cvsroot/pgsql/doc/src/sgml/installation.sgml,v 1.30 2000/11/30 21:44:07 petere Exp $ -->
+<!-- $Header: /cvsroot/pgsql/doc/src/sgml/installation.sgml,v 1.31 2000/12/03 14:41:47 thomas Exp $ -->
 
 <chapter id="installation">
  <title><![%flattext-install-include[<productname>PostgreSQL</>]]> Installation Instructions</title>
@@ -1160,6 +1160,13 @@ gunzip -c user.ps.gz \
 	<entry>2000-04-12, Tom Lane (<email>tgl@sss.pgh.pa.us</>)</entry>
         <entry>See also <filename>doc/FAQ_HPUX</></>
        </row>
+       <row>
+	<entry>IBM</entry>
+	<entry>S/390</entry>
+	<entry>7.1</entry>
+	<entry>2000-11-17, Neale Ferguson (<email>Neale.Ferguson@softwareAG-usa.com</>)</entry>
+	<entry></>
+       </row>
        <row>
 	<entry>IRIX 6.5.6f</entry>
 	<entry>MIPS</entry>
diff --git a/src/include/storage/s_lock.h b/src/include/storage/s_lock.h
index d50e3564bb..863801f8ee 100644
--- a/src/include/storage/s_lock.h
+++ b/src/include/storage/s_lock.h
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/include/storage/s_lock.h,v 1.74 2000/11/28 23:27:57 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/include/storage/s_lock.h,v 1.75 2000/12/03 14:41:42 thomas Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -128,6 +128,29 @@ __asm__("swpb %0, %0, [%3]": "=r"(_res), "=m"(*lock):"0"(_res), "r" (lock));
 
 #endif   /* __arm__ */
 
+#if defined(__s390__)
+/*
+ * S/390 Linux
+ */
+#define TAS(lock)      tas(lock)
+
+static inline int
+tas(volatile slock_t *lock)
+{
+ int _res;
+
+        __asm__ __volatile("    la    1,1\n"
+                           "    l     2,%2\n"
+                           "    slr   0,0\n"
+                           "    cs    0,1,0(2)\n"
+                           "    lr    %1,0"
+                           : "=m" (lock), "=d" (_res)
+                           : "m" (lock)
+                           : "0", "1", "2");
+
+       return (_res);
+}
+#endif  /* __s390__ */
 
 
 #if defined(__sparc__)