Need to remove HTC messaging because of serious lag

[kfcherry]

I have noticed that once I get about 50 or so text messages in a conversation with one person the phone starts to seriuosly lag when I try to go back to the home screen (sometimes it takes a minute). I installed the zenyee 1.2 cab and it seeemed to default the phone to the windows text function (which I want), but as soon as I sent a picture mail the phone was back to the HTC messaging program. I ran the cab to uninstall the Sprint picture mail program and installed the arcsoft mms cab, but for some reason I am still stuck with HTC's slow messaging program. I spoke with both Sprint and HTC regarding this and their solution is to delete old text messages. Can anyone help??