Since version 1.9.5, notification system on Pure messenger is totally independant for all widgets.
The problem is: you can have/forgot a widget on another Home, or you can have a partially configured widget somewhere in memory which HAVE notifications enabled.
There is 2 solutions to disable those old widgets notifications:
1 – enter the widget config panel, press menu key, tap ‘kill old widgets’
2 – enter the widget config panel, export your widget settings, uninstall the application, reinstall it from the market, insert a fresh widget and restore settings.
Another thing, be sure you have disabled notifications from incoming apps (gmail, K9FP, SMS …) to avoid multiple notifications if you enabled them in Pure messenger widget.
If you don’t want notifications from Pure messenger, be sure you disable all providers for notification 1 & 2 in Pure messenger configuration panel.