Whoops - yeah, he's using Xalan 2.1.0 We were able to fix it by doing a clean install of Ant. I then added the various custom/third party jars our Ant scripts rely on to the ant/lib directory. Everything works fine now - really odd, and I'd love to know what was going on, but in the end, it works. Thanks, Kyle >>> stephane.bailliez@haht.com 07/03/02 06:26AM >>> > -----Original Message----- > From: Kyle Adams [mailto:kadams@gfs.com] > > We've got a real puzzler on our hands - our build scripts use XSLT to > generate on the fly. One of our developers (so far, the only one) > consistently gets the following stack trace when he tries to build: > > He's got Ant 1.4.1, running on Windows NT 4, using Xalan 1.2.2 (I > think, though I'm not quite sure about that one). You are using Xalan 1.2 only if you use