Hi Rolly,
Problem solved -> this was a plugin which had a bug in it.
It works now, thanks for your support.
The problem has been somehow resolved. Without turning off the plugins.
Thanks
I also encounter this error, since yet seen only in the Plugins -> Add New screen.
[Wed May 02 22:14:22 2012] [error] [client 127.0.0.1] PHP Warning: number_format() expects parameter 1 to be double, string given in /xxxxx/wp-includes/functions.php on line 155, referer: http://xxxx/wp-admin/plugins.php
