I want to install STS on Eclipse 3.8.0, because of a drastic performance decrease in 4.2 specially it's new UI model. I downloaded and installed classic eclipse 3.8.0 and installed WTP and m2e on it.

Now when I want to install STS 3.0, I first told that atlassian connector is required. After installing atlassian connector no I receive the following errors which prevent installing STS:

Code:
Cannot complete the install because of a conflicting dependency.
  Software being installed: Spring Tool Suite Package 3.0.0.201208091018-RELEASE-e42 (org.springsource.sts.package.feature.group 3.0.0.201208091018-RELEASE-e42)
  Software currently installed: Eclipse Platform 3.8.0.I20120608-1200 (org.eclipse.platform.ide 3.8.0.I20120608-1200)
  Only one of the following can be installed at once: 
    Eclipse Platform 4.2.0.v201206081400 (org.eclipse.platform 4.2.0.v201206081400)
    Eclipse Platform 3.8.0.v201206081200 (org.eclipse.platform 3.8.0.v201206081200)
  Cannot satisfy dependency:
    From: Eclipse Platform 3.8.0.v20120607-071945-9gF7jI7nG5qByXMVdkhRMWBQlF4PnDCLybDCPQ (org.eclipse.platform.feature.group 3.8.0.v20120607-071945-9gF7jI7nG5qByXMVdkhRMWBQlF4PnDCLybDCPQ)
    To: org.eclipse.platform [3.8.0.v201206081200]
  Cannot satisfy dependency:
    From: Eclipse Platform 4.2.0.v20120608-135145-9JF7BHV8FyMteji0Oi_ePMz0xuZ8TVo7lV0z0ecb (org.eclipse.platform.feature.group 4.2.0.v20120608-135145-9JF7BHV8FyMteji0Oi_ePMz0xuZ8TVo7lV0z0ecb)
    To: org.eclipse.platform [4.2.0.v201206081400]
  Cannot satisfy dependency:
    From: Eclipse Platform 3.8.0.I20120608-1200 (org.eclipse.platform.ide 3.8.0.I20120608-1200)
    To: org.eclipse.platform.feature.group [3.8.0.v20120607-071945-9gF7jI7nG5qByXMVdkhRMWBQlF4PnDCLybDCPQ]
  Cannot satisfy dependency:
    From: Spring Tool Suite Package 3.0.0.201208091018-RELEASE-e42 (org.springsource.sts.package.feature.group 3.0.0.201208091018-RELEASE-e42)
    To: org.eclipse.platform.feature.group [4.2.0.v20120608-135145-9JF7BHV8FyMteji0Oi_ePMz0xuZ8TVo7lV0z0ecb]