Would it be possible to make use of compression for CVS optional?
It should be as simple as adding checkbox to the project configuration page and
modifying compression() method in hudson.scm.CVSSCM.java
It would allow to switch of compression where it can't be used for various reasons.

private String compression()

{ // CVS 1.11.22 manual: // If the access method is omitted, then if the repository starts with // `/', then `:local:' is assumed. If it does not start with `/' then // either `:ext:' or `:server:' is assumed. boolean local = cvsroot.startsWith("/") || cvsroot.startsWith(":local:") || cvsroot.startsWith(":fork:"); // For local access, compression is senseless. For remote, use z3: // http://root.cern.ch/root/CVS.html#checkout return local ? "-z0" : "-z3"; }

Thanks.