[squid-users] FTP Whitelist hostnames vs ip

I have a whitelist to allow users to access only sites required. We primarily use it for ftp, either through a web browser or filezilla-like clients. The browser based is flawless, but odd behavior with ftp clients.
acl whitelist dstdomain "/etc/squid3/whitelist"
http_access deny !whitelist
Whitelist contains (for testing):
gatekeeper.dec.com

Here is the result:
1311886691.258 21738 192.168.100.194 TCP_MISS/200 998 CONNECT gatekeeper.dec.com:21 - DIRECT/192.6.29.21 -
1311886757.392 0 192.168.100.194 TCP_DENIED/403 1899 CONNECT 192.6.29.21:51967 - NONE/- text/html

As you can see, it changes from using hostname to IP address, which matches nothing in the whitelist, and is denied. If I add the IP to the whitelist, it works perfectly. How can I force it to always use the hostname?
IP added to whitelist:
1311887068.133 17458 192.168.100.194 TCP_MISS/200 1919 CONNECT gatekeeper.dec.com:21 - DIRECT/192.6.29.21 -
1311887072.841 124 192.168.100.194 TCP_MISS/200 0 CONNECT 192.6.29.21:51255 - DIRECT/192.6.29.21 -

Scott Mace
Infrastructure and Security Analyst
RenewData
512.276.5500 x 3244 Phone
512.276.5555 Fax
512.299.4439 Cell
scott.mace_at_renewdata.com
http://www.renewdata.com

Global in reach. Local in focus.

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Received on Thu Jul 28 2011 - 21:05:42 MDT