krb5 security and bug fix update

[1.6.1-70.el5]

• add upstream patch for telnetd buffer overflow (CVE-2011-4862, #770351)
  [1.6.1-69.el5]
• ftp: fix a static analysis should-never-happen NULL dereference (#750823)
  [1.6.1-68.el5]
• backport fixes to teach libkrb5 to use descriptors higher than FD_SETSIZE
  to talk to a KDC by using poll() if it’s detected at compile-time, revised
  (#701444, RT#6905)
  [1.6.1-67.el5]
• add backported patch by way of jbarbuc to free subkeys created by the
  KDC while processing TGS requests (#708516)
  [1.6.1-66.el5]
• add backported patch by way of several people to better avoid false
  detection of replay attacks when talking to systems with coarse time
  resolution (#713500)
  [1.6.1-65.el5]
• ftpd: add backported patch to check for errors when calling setegid
  (MITKRB5-SA-2011-005, CVE-2011-1526, #719098)
  [1.6.1-64.el5]
• klist: don’t trip over referral entries when invoked with -s (#729067,
  RT#6915)