Restore HPUX FAQ entry that talked about working around regression

script problems, because in 8.1.X, the regression test is still a
script.  Patch to 8.1.X only.

doc/FAQ_HPUX

@@ -3,7 +3,7 @@ Frequently Asked Questions (FAQ) for PostgreSQL 7.3
 HP-UX Specific
 TO BE READ IN CONJUNCTION WITH THE NORMAL FAQ
 =======================================================
-last updated:           $Date: 2006/10/10 00:29:14 $
+last updated:           $Date: 2006/10/10 20:11:44 $
 
 current maintainer:     Tom Lane (tgl@sss.pgh.pa.us)
 original author:        Tom Lane (tgl@sss.pgh.pa.us)
@@ -84,3 +84,19 @@ low-order-digit differences in the geometry tests, which vary depending
 on which compiler and math library versions you use.
 
 Any other error is cause for suspicion.
+
+The parallel regression test script (gmake check) is known to lock up
+on PA-RISC when run under HP's Bourne shells: /usr/bin/sh and
+/sbin/sh. To fix this problem, you will need PHCO_30269 with its
+dependent patch or successor patches:
+
+    PHCO_30269  s700_800 cumulative sh-posix(1) patch
+    PHCO_29816  s700_800 rc(1M) scripts cumulative patch 
+
+To work around this problem, use ksh to run the regression script:
+
+	gmake SHELL=/bin/ksh check
+
+If you see that the tests have stopped making progress and only a shell
+process is consuming CPU, kill the shell process and start over with the
+above command.