Forum OpenACS Development: Re: Bug in xowiki page includelets resolution when veiwing live revision
Note, as indicated before, an updated xotcl-core is not sufficient, xowiki should be updated as well. Note that the mentioned patch was between xowiki-procs 1.122 to 1.223. xowiki-procs is in head at version 1.306.
Not sure, what xowiki version you are using. It might be easier to upgrade xotcl-core and xowiki to HEAD.