We'd have to see how gaim is rewriting the application file. If it is doing open/truncate/write/close, there will always be the chance that the file would be lost if you crash right after the truncate. This is true with both ext3 and ext4. With the workaround, the chances of losing the file with ext4 when the application tries to do the fundamentally broken replace-via-truncate are the same as with ext3. We can't do better than that.