It should only take that long to open on the first time after a reboot. Well mine usually takes 5 seconds. But since WM5 doesnt close the app it will sit in the background and should open quite readily there-after.
If the 6-7 seconds after a reboot is tiresome, then I think your best solution would be to keep the inbox clean or perhaps divide the messages into sub folders. Thats about the best I think your going to get as I really havent seen any sms tweaks kicking around.
Device: Omnia 7
From the ancient Mpx200 to Omnia 7
and everything in between...
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