The problem occured while using the Live USB. I did not do an install yet, so I can't change things.
Not a direct question for help. I got a tip from De Baas from the Dutch PCLOS forum I did not try yet. The tip was:
Make wired connection with the internet, via synaptic install dkms-r8192se, configure wireless via PPC and it should be working. If I do an install of Gnome MMXII right afther that the change should be effective after the install as well, because depending on the memory capacity of the hardware this can stay in the memory and therefore used during the install by PCLOS.
I had a similar experience with that before, because in earlier installs my wireless password etc. was remebered and I had instant wireless connection with my router after a fresh install without entering username and password after the first log in. So I think it can work if the install of dkms-r8192se is working. I will try this later, because I am working with Mint 12 Gnome and trying Mate/Cinnamon/Unity to find out what I like best.
But PCLOS Gnome is still my favourite, therefore I tried the Live USB MMXII.
The wireless controller is:
Realtek Semiconductor Co.LTD RTL 8191 SEvB Wireless Lan Controller.