I am trying to figure out an issue. My internet is working fine, but this one website is not resolving. It works via a proxy, traceroute works:

 1  192.168.1.1 (192.168.1.1)  4.205 ms  0.568 ms  0.510 ms
 2  * * *
 3  67.59.255.13 (67.59.255.13)  10.583 ms  7.949 ms  7.557 ms
 4  67.59.255.61 (67.59.255.61)  10.256 ms  9.576 ms  13.083 ms
 5  64.15.8.126 (64.15.8.126)  9.943 ms  11.929 ms  11.452 ms
 6  64.15.0.217 (64.15.0.217)  14.655 ms  14.092 ms  13.771 ms
 7  64.15.0.118 (64.15.0.118)  33.201 ms  34.875 ms  36.544 ms
 8  xe-6-0-3.ar1.ord1.us.nlayer.net (69.31.111.169)  34.027 ms  34.957 ms  34.231 ms
 9  ae1-30g.cr1.ord1.us.nlayer.net (69.31.111.133)  82.683 ms  35.138 ms  37.592 ms
10  xe-3-0-0.cr2.iad1.us.nlayer.net (69.22.142.26)  41.657 ms  34.063 ms  34.519 ms
11  ae2-30g.ar2.iad1.us.nlayer.net (69.31.31.186)  35.780 ms  36.361 ms  33.968 ms
12  as33597.xe-3-0-7.ar2.iad1.us.nlayer.net (69.31.30.230)  35.086 ms
as33597.xe-3-0-7.ar2.iad1.us.nlayer.net (69.31.30.234)  38.031 ms
as33597.xe-3-0-7.ar2.iad1.us.nlayer.net (69.31.30.230)  36.833 ms
13  cr1.iad2.inforelay.net (66.231.176.246)  32.595 ms
cr2.iad1.inforelay.net (66.231.176.10)  31.771 ms
cr1.iad2.inforelay.net (66.231.176.246)  32.622 ms
14  cr1.iad2.inforelay.net (66.231.176.246)  32.956 ms  33.625 ms !X  41.058 ms
15  * cr1.iad2.inforelay.net (66.231.176.246)  35.312 ms !X *
16  * cr1.iad2.inforelay.net (66.231.176.246)  32.814 ms !X *
17  cr1.iad2.inforelay.net (66.231.176.246)  35.459 ms !X *  53.137 ms !X

Ping returns this:

Request timeout for icmp_seq 0
Request timeout for icmp_seq 1
Request timeout for icmp_seq 2
Request timeout for icmp_seq 3
Request timeout for icmp_seq 4
Request timeout for icmp_seq 5
Request timeout for icmp_seq 6

But what I can not figure out is why my browsers (Firefox, Safari, Opera) can not resolve the domain. I am on a Wifi connection. What could be the problem?

BTW I am on a Mac (10.6.5)