The JDeveloper extension API has undergone extensive changes in between versions. You are right, this plugin will not work with the 10.1.2 version of JDeveloper and support for this feature is not planned. I'm sorry.
I will however, recommend that you download the latest production release of JDeveloper, as it holds a lot of improvements and is, in my opinion, the very best IDE for java development around.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
JDev VSS Extension not working for JDeveloper 10.1.2. Please provide pointers to this issue
Please examine this support request:
https://sourceforge.net/tracker/index.php?func=detail&aid=1469291&group_id=164706&atid=832800
The JDeveloper extension API has undergone extensive changes in between versions. You are right, this plugin will not work with the 10.1.2 version of JDeveloper and support for this feature is not planned. I'm sorry.
I will however, recommend that you download the latest production release of JDeveloper, as it holds a lot of improvements and is, in my opinion, the very best IDE for java development around.