I am trying to install from the archive, and I get:
Unsatisfied dependency: [com.genuitec.myeclipse.enterprise.workbench.feature.group 7.0.0.zmyeclipse70020081206] requiredCapability: org.eclipse.equinox.p2.iu/org.mozilla.xulrunner.gtk.linux.x86/[1.8.1.3-20070404,1.8.1.3-20070404]
My installation is Eclipse 3.4.1 from the Fedora folks, with Aptana Pro installed.