Time to update your bookmarks once again.
The new URL of the AHI Homepage is: http://arp2.berlios.de/ahi/
From AHI Homepage:
2006-07-26: Unfortunately, it looks like Lysator's project web servers will be off-line for quite some time, perhaps forever. What a shame, considering that Lysator had Sweden's first web server online back in february 1993 — server number 10 in the world. AHI has now moved completely to Berlios; sadly, that means that the old v4 site is gone (at least until I can find a server that still runs Roxen 1.3).