can't login after upgrade to custom firmware

Hello,

I have upgraded my Asus WL300g firmware with the firmware provided at http://oleg.wl500g.info/ because I want to use it as a client station.

After the upgrade the AP rebooted.
I could not login with my old user/pass or admin/admin on both HTTP and telnet. After some tries telnet suddenly worked with admin/admin. I configured some things on the wireless interface (using wl) and wanted to test whether they stayed after a reboot.

After the reboot I couldn't login at all.
I have reset the AP by pressing the reset button while switching it on. The power led started to blink after that and it kept doing that for a few hours, when I switched the AP off.

After boot all leds were on, as usual. Still I can't login to telnet or HTTP with either admin/admin or my old user/pass.

What could have caused my problem and how could I solve it?