You can specify a revision within the svn:external property. Something like (got this sample from the svn book):
> -----Oorspronkelijk bericht----- > Van: Carsten Ziegeler [mailto:[EMAIL PROTECTED] > Verzonden: vrijdag 23 september 2005 11:49 > Aan: Cocoon-Dev > Onderwerp: [RT] Are svn externals a good idea? > > I'm just wondering if svn externals are a good idea wrt to versioning. > I just had to checkout an older version of 2.1.8-dev and checked out > that particular revision. Now unfortunately, the jcr block (and now the > forms block) is linked into the tree using a svn external. And although > I checked out an old version of the cocoon tree, I get the latest > version from the jcr block. So it's not that easy to get the exact > version of the whole tree. Or is there an easy way? > > And what does this mean wrt to tagging a release (which is a copy of the > source tree)? > > Carsten > -- > Carsten Ziegeler - Open Source Group, S&N AG > http://www.s-und-n.de > http://www.osoco.org/weblogs/rael/