Ant 1.4 -- failonerror attributes?

[J.D. Fagan]

Unfortunately, I'm stuck on a VSS based project at the moment :-(  And I'm
trying to build a target that depends on a VSS checkout.

How can I ignore an error from vsscheckout and continue on?  My error
sometimes occur when I already have a file checked out, and thus, just want
to ignore this error and continue on.  I think I might be asking for the
"failonerror" capability of javac task?  Anyone have any insight?

JD