Eclipse: How can I install UML2 Tools - eclipse

Question

I'd like to try UML2 Tools for Eclipse, as shown in this tutorial.
I currently have Eclipse 3.6 Helios for Java EE developers.
In my Eclipse Marketplace I switched marketplace catalog to Yoxos Marketplace and there searched for UML2 Tools SDK(Incubation). When I try to install them, Eclipse wont proceed and complains about some conflicting dependencies. Here's whole trace:
Cannot complete the install because of a conflicting dependency.
Software being installed: UML2 Tools SDK (Incubation) 0.9.0.v200906190654 (org.eclipse.uml2tools.sdk.feature.group 0.9.0.v200906190654)
Software currently installed: Eclipse IDE for Java EE Developers 1.3.2.20110301-1807 (epp.package.jee 1.3.2.20110301-1807)
Only one of the following can be installed at once:
EMF Ecore 2.5.0.v200906151043 (org.eclipse.emf.ecore 2.5.0.v200906151043)
EMF Ecore 2.6.1.v20100914-1218 (org.eclipse.emf.ecore 2.6.1.v20100914-1218)
EMF Ecore 2.6.0.v20100614-1136 (org.eclipse.emf.ecore 2.6.0.v20100614-1136)
Cannot satisfy dependency:
From: Eclipse IDE for Java EE Developers 1.3.2.20110301-1807 (epp.package.jee 1.3.2.20110301-1807)
To: org.eclipse.epp.package.jee.feature.feature.group [1.3.2.20110301-1807]
Cannot satisfy dependency:
From: Object Constraint Language (OCL) 2.0 Compatibility API 1.1.101.v200901271800 (org.eclipse.emf.ocl 1.1.101.v200901271800)
To: bundle org.eclipse.ocl.ecore [1.1.0,2.0.0)
Cannot satisfy dependency:
From: Java EE IDE Feature 1.3.2.20110301-1807 (org.eclipse.epp.package.jee.feature.feature.group 1.3.2.20110301-1807)
To: org.eclipse.jst.enterprise_ui.feature.feature.group 0.0.0
Cannot satisfy dependency:
From: Eclipse Java EE Developer Tools 3.2.3.v201011031800-7b7GHfIFSK2WBRT6E1mcyFXGPnSh (org.eclipse.jst.enterprise_ui.feature.feature.group 3.2.3.v201011031800-7b7GHfIFSK2WBRT6E1mcyFXGPnSh)
To: org.eclipse.jst.ws.jaxrs.ui [1.0.301.v201012020511]
Cannot satisfy dependency:
From: JAX-RS Tools - UI 1.0.301.v201012020511 (org.eclipse.jst.ws.jaxrs.ui 1.0.301.v201012020511)
To: bundle org.eclipse.emf.ecore [2.6.0,3.0.0)
Cannot satisfy dependency:
From: OCL 2.0 Binding for Ecore 1.3.0.v200905271400 (org.eclipse.ocl.ecore 1.3.0.v200905271400)
To: bundle org.eclipse.emf.ecore [2.5.0,2.6.0)
Cannot satisfy dependency:
From: UML2 Diagramming (Incubation) 0.9.0.v200906190654 (org.eclipse.uml2.diagram.feature.group 0.9.0.v200906190654)
To: org.eclipse.emf.ocl 0.0.0
Cannot satisfy dependency:
From: UML2 Tools SDK (Incubation) 0.9.0.v200906190654 (org.eclipse.uml2tools.sdk.feature.group 0.9.0.v200906190654)
To: org.eclipse.uml2.diagram.feature.group [0.9.0.v200906190654]
Maybe I don't understand whole concept and am trying something inappropriate, I don't know. Thank you for advices.

Answer 1

UML2 Tools has no release that works with Eclipse 3.6 and newer. You could use Papyrus instead.

Answer 2

If you really need UML2 Tools 0.9.0 to work in Eclipse Helios 3.6, there is a workaround you need to do before installing UML2 Tools as explained in this answer.