Too many fails after validation test!

[Mehdi Hashemian <mhashemi@catarina.usc.edu>]

hi,
i got like 13 of tests failed after validation test of ns-2.1b5! Would 
you please give me some hints? i have just started working with ns.
here are all tests that failed:
 
validate overall report: some tests failed:
     ./test-all-simple ./test-all-tcp ./test-all-red ./test-all-sack
./test-all-schedule ./test-all-cbq ./test-all-rbp ./test-all-tcp-init-win
./test-all-tcpVariants ./test-all-ecn ./test-all-manual-routing
./test-all-newreno ./test-all-ecn-ack
7162.250u 225.700s 2:13:05.67 92.5% 0+-507k 249+23411io 614pf+0w
Exit 1

thanx
mehdi