No tool is perfect, and I'm about to start several long-term projects using Trac, and wanted a heads up of the kinds of problems I may or may not experience with it. In other words, Trac meets my needs in the short term, and I've already made the decision to use it, but I want to know what to expect down the road.

I am not looking for:

• "Use product X instead of Trac because..." answers.
• "Trac is great because..." answers.
• A comparison to any other specific system.
• "Trac doesn't support Feature X" answers. I can read the feature list too, thank you very much.

I am looking for:

• "Feature X does not behave as expected..."
• "Trac behaves oddly when..."
• "Trac doesn't fully support..."
• "Trac itself has a known bug that will likely never be fixed..."
• And especially "Trac can't handle..."
• etc

So, what Trac-induced headaches do I have to look forward to?

For future reference, this question was asked while Trac v0.11 was the latest stable release.