CVS - check revision number of file is valid

[Sunil Saxena]

hi,

i am making a build application
CVS is used as repository along with ANT scripts to checkout file revision
from CVS.

Following command is used:
<cvs cvsRoot="${cvs.root}" command="checkout -r ${file.revision.number}
${file.path}/${file.name}" dest="${build.src.path}" > </cvs>

Error message is thrown by CVS when file-name of file-path is incorrect.
But only get warning message when revision number of file-name is incorrect
.

Is there a way to generate error if the file-revision number of file is
incorrect ??
Would like the build to fail if the file-name /  revision number of file is
invalid.

Regards,
Sunil