Apparently ipaddr works. 20090910 git + patches realms.c { "src_ipaddr", PW_TYPE_STRING_PTR, 0, &hs_srcipaddr, NULL }, Is this correct? This is the bt #0 0xb7cab8eb in strlen () from /lib/i686/cmov/libc.so.6 #1 0xb7c78198 in vfprintf () from /lib/i686/cmov/libc.so.6 #2 0xb7c982e4 in vsnprintf () from /lib/i686/cmov/libc.so.6 #3 0xb7c7e602 in snprintf () from /lib/i686/cmov/libc.so.6 #4 0x08056039 in listen_alloc (type_name=0x1 <Address 0x1 out of bounds>) at listen.c:666 #5 0x08056dac in proxy_new_listener (ipaddr=0x809b1bc, exists=1) at listen.c:830 #6 0x0806b60e in home_server_create_callback (ctx=0x81e72c8, data=0xbffff3a0) at realms.c:2231 #7 0xb7fd1c0e in WalkNodeInOrder (X=0x809b4a0, callback=0x806b5d0 <home_server_create_callback>, context=0x81e72c8) at rbtree.c:544 #8 0x0806b594 in home_server_create_listeners (ctx=0x81e68a0) at realms.c:2261 #9 0x080569ca in listen_init (config=0x8081020, head=0xbffff718) at listen.c:1262 #10 0x08069dcf in radius_event_init (cs=0x8081020, spawn_flag=0) at event.c:3597 #11 0x0805e728 in main (argc=2, argv=0xbffff8b4) at radiusd.c:346