vcs2008.09安装问题

我在CentOS5.5下安装design compiler 2008.09和vcs 2008.09后，dc_shell可以正常运行，但执行vcs tst.v时出现以下错误。
感觉好像是操作系统的问题。请高人现身，指点迷津。
/eda/synopsys/vcs_vA-2008.09/bin/vcs: line 876: dc: command not found
Chronologic VCS (TM)
Version A-2008.09 -- Mon Jan3 17:08:30 2011
Copyright (c) 1991-2008 by Synopsys Inc.
ALL RIGHTS RESERVED
This program is proprietary and confidential information of Synopsys Inc.
and may be used and disclosed only as authorized in a license agreement
controlling such use and disclosure.
The design hasn't changed and need not be recompiled.
If you really want to, delete file csrc/.vcs.timestamp and
run VCS agAIn.
/eda/synopsys/vcs_vA-2008.09/bin/vcs: line 876: dc: command not found
/eda/synopsys/vcs_vA-2008.09/bin/vcs: line 876: dc: command not found
/eda/synopsys/vcs_vA-2008.09/bin/vcs: line 876: dc: command not found
/eda/synopsys/vcs_vA-2008.09/bin/vcs: line 876: dc: command not found
/eda/synopsys/vcs_vA-2008.09/bin/vcs: line 876: dc: command not found
gcc-pipe -O -I/eda/synopsys/vcs_vA-2008.09/include-c -o rmapats.o rmapats.c
if [ -x ../simv ]; then chmod -x ../simv; fi
g++-o ../simvrmapats_mop.o rmapats.o 5rmr_1_d.o SIM_l.o 5NrI_d.o 5NrIB_d.o/eda/synopsys/vcs_vA-2008.09/linux/lib/libvirsim.a /eda/synopsys/vcs_vA-2008.09/linux/lib/librterrorinf.so/eda/synopsys/vcs_vA-2008.09/linux/lib/libvcsnew.so/eda/synopsys/vcs_vA-2008.09/linux/lib/ctype-stubs_32.a -ldl-lc -lm -ldl
/usr/bin/ld: warning: libstdc++.so.5, needed by /eda/synopsys/vcs_vA-2008.09/linux/lib/librterrorinf.so, may conflict with libstdc++.so.6
../simv up to date

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