So here is my problem, I'm absolutely unable to connect to a FTP server, in circumstances I've never seen before. Here is the situation :

• I get a "Connection timed out" just after the MLSD command.
• I usually use Filezilla, under Ubuntu, but to make sure the problem isn't related to this particular client I tried a few others : gftp on ubuntu and winscp and freeftp on windows 7. All the same result.
• Also made sure to try with Active or Passive modes. Same result.
• At this point I would be inclined to think there is something wrong with my current network (furthermore, according to a coworker the FTP server is OK). But I did check with http://ftptest.net/ and I am able to get the directory listing (which I'm not able to through a FTP client).

So in the end the last thing I didn't tried is to go on another network, solution which seems would work, but wouldn't be very practical in the long run. And thus I guess there's something wrong with my router... but what could it possibly be?

Note : I did try to register and post this question on filezilla's board first... but I can't create an account with a gmail nor hotmail account. WTF?