Tape backup question -- getting the correct mtime after restoring

[My name is already in the article, you stupid postnews program]

When I restore from a tape backup for the 3b1 all the mtime's of the restored
files are set to the time of the restore rather than the original mtime of the
file when it was backed up.  Can this be fixed?  Is there some parameter to
tapecpio (which is undocumented, BTW) that will give me the original mtimes
when I restore?  Is it something that has to be done during back up or during
the restore?

Bob Wilber   wilber at research.att.com   {att-gateway}!gauss!wilber