Error trying to import a a daml file in protege

I'm tr开发者_JAVA技巧ying to import a daml file (.daml) in protege, but I get the following exception:

Exception in thread "AWT-EventQueue-0" java.lang.noClassDefFoundError: org/apache/xerces/utils/URI$MalformedURIException 
at edu.standford.smi.protegex.storage.daml.DAMLJenaParser.jenaparse(DAMLJenaParser.java:49)...

Does any of you know how to get around this? Does any of you know any other powerful ontology app. dvelopment environment other than protege for developing daml+oil documents? Please reply as soon as you can. Thanks in advance.

Its solved. I new I needed xerces but did not know exactly which version. As my version of protege (portege 1.9 2000) is an old one it seems that I needed an old version of xerces. I just did not know which one. Now, its working fine. I think the version of xerces is 1.4x

Thanks for your time.