we implemented a checkin policy in our svn server. every checkin comment must fulfill these policy. otherwise the checkin is denied, the svn server genarates an error message for the client.
this policy works fine, the error message is shown for example in tortoise client.

then i tried to create a svn tag branch out of the jenkins gui "tag this build", my checkin comment does not match the policy. the tag was not created, but the error message of the svn server was not visible in jekins. nor did jenkins report the failure during the creation of the svn branch in any way.
took me some time, to figure out why the branch was not created.