I minimize KMail to the tray icon, and then click on that icon to maximize it. Which works very well, except for a small problem: I have four desktops, and sometimes clicking the KMail tray icon will maximize it... but not in the current desktop! For instance, suppose I open KMail in desktop 1, and then minimize (to tray), and then go to desktop 2, and click the tray icon, KMail's window will show up maximized, but in desktop 1!

I've tweaked with windows settings and behaviour, but I can't get KMail to stop switching to another desktop. This doesn't happen always, though it becomes very much annoying when it does. Besides KMail, I also use amarok and and MKess minimized to tray, but none of them exhibit the same behaviour (i.e. they always maximize on the current desktop). Ideas anyone?

I'm using KDE 4.3.4 (ArchLinux) and KMail 1.12.4

It is probable that KMail remembers the virtual desktop its window was in and restores to it.

Can you see if you can reproduce this with KDE SC 4.4, and if so, file a bug at bugs.kde.org? Note that KMail2 is likely to be used in 4.5 however, which may mean that the bug has been fixed.

I was able to reproduce the same behaviour in 4.4.

Yes maybe this issue will be solved in KMail2, but in the meantime, and on a related note, when I click on the icon to start Kile, the application is always launched in the virtual desktop where it last ran. No tray icons are involved, I just click on its icon and it goes to run in the desktop where it previously was. Which is somewhat odd, because I would expect it as default behaviour to run in the current desktop, and not memorize the previous one...

This is possibly an expected behaviour of KDE SC applications. Can you check to see if some pure Qt applications do the same?