I almost thought I had something there.  Here’s what I did:

Attempted to install subversive from:

http://download.eclipse.org/technology/subversive/0.7/update-site/

Got the following error message:

Subversive SVN JDT Ignore Extensions (Optional) (Incubation) (0.7.7.I20090224-1900) requires plug-in “org.eclipse.jdt.core”.

Installed Java Development Tools from Eclipse software updates:

Europa Discovery Site
Java Development
Eclipse Java Development Tools 3.3.2r33x_r20080129-..

This hung while using IBiblio.   I restarted FlexBuilder and tried again.  This time using xmission.  Much better, and successfull.  FlexBuilder rebooted and then I went to the polarion update site above for Subversive and successfully installed.  Rebooted again, and right click on my project:

Team > Share Project

Entered my credentials, but then, bam:

Share project was failed.
Share project was failed.
Selected SVN connector library is not available or cannot be loaded.
If you selected native JavaHL connector, please check if binaries are available or install and select pure Java Subversion connector from the plug-in connectors update site.
If connectors already installed then you can change the selected one at: Window->Preferences->Team->SVN->SVN Client.

Selected SVN connector library is not available or cannot be loaded.
If you selected native JavaHL connector, please check if binaries are available or install and select pure Java Subversion connector from the plug-in connectors update site.
If connectors already installed then you can change the selected one at: Window->Preferences->Team->SVN->SVN Client.

The duplication is odd, but I don’t know if it’s symptomatic of anything.

U can’t believe FlexBuilder doesn’t have support for subversion, but I can believe Eclipse is borked enough to fail on something trivial like this without any help from Adobe.