Comment 8 for bug 455911

Well, there is the problem - a person may not know that they must install eclipse-pdt (or the full eclipse package) when they want to use the JDT with some external plugin (let's say, mylyn for example, which is not provided by Ubuntu).

Use case:
1. The user wants to use just Eclipse JDT with Mylyn and maybe Subversive,
2. The user installs eclipse-jdt (she doesn't know what eclipse-pdt does and rather wants to avoid installing redundant stuff on her small netbook).
3. The user then goes and ads the Mylyn update site as per the instructions on Mylyn site
4. The user selects to install the Mylyn plugins and presses Next.

The result - an obscure error message.

As installing plugins is an accepted use of Eclipse, there should either be a more understandable error message (this is probably out of scope of Ubuntu developers, I believe), or the eclipse-jdt package should enforce installing eclipse-pdt somehow