Bluetooth: can not receive files from tablet Android 4.0

[linuxfluesterer]

Hallo....
I've a strange problem. I've setup my (external) bluetooth usb ministick. It is recognized by KDE and I can use it with my China mobile A9220 (Android 2.3.6 upgradet to fake 4.0)
With that phone I am paired and I can send files from it to my directory which is set in KDE Bluetooth settings.
Now I could pair my tablet (German brand Medion P9514) because it was found by kde.
But first for pairing, I must put in a manual pin; with my A9220 phone, I was given a random pin which I should confirm in both, KDE and A9220 also.
So, I enter 1234 in KDE and in tablet and click Next; then KDE asked me for service (Send or DUN) and I decide for Send.
Then I want to send a photo from my tablet to KDE like I did with my phone.
The tablet says 'Sending file xyz.jpg' and in KDE Task line I see that bt is paired for 1 or 2 seconds.
And then the tablet says: 'File xyz.jpg was not sent' ...
The main problem is, I can not delete any phone, computer or tablet entry in the bt list of that tablet.
I can unpair ... but it seems to remember any bt device id and it's pairing pin maybe also.
What can I do???

-Linuxfluesterer (I love KDE ...)