pull up r24470 from trunk

pull up r24470 from trunk

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 r24470 | ghudson | 2010-10-22 20:38:17 -0400 (Fri, 22 Oct 2010) | 10 lines

 ticket: 6810
 subject: Better	libk5crypto NSS	fork safety
 target_version:	1.9
 tags: pullup

 Use SECMOD_RestartModules() from the forthcoming NSS 3.12.9 release to
 make the libk5crypto back end work after a fork.  Add a test program
 to exercise fork detection in the NSS back end.  Add a configure-time
 version check to ensure that we're using NSS 3.12.9 or later.

ticket: 6810
version_fixed: 1.9
status: resolved

git-svn-id: svn://anonsvn.mit.edu/krb5/branches/krb5-1-9@24495 dc483132-0cff-0310-8789-dd5450dbe970