Hi,
F5 wouldn't support you adding your own modules, but it should just work if you upload it and call it from your script.
Else it looks like the curl executable already installed might support it if you set CURLOPT_CONNECTTIMEOUT_MS as an environmental variable.
http://stackoverflow.com/questions/6211282/why-would-curl-time-out-in-1000ms-when-i-have-set-up-timeout-upto-3000ms
Check the version of your CURL and PHP installation. CURLOPT_CONNECTTIMEOUT_MS added in cURL 7.16.2. Available since PHP 5.2.3. http://php.net/manual/en/function.curl-setopt.php
tmsh show sys version
Sys::Version
Main Package
Product BIG-IP
Version 11.4.0
Build 2384.0
Edition Final
Date Thu May 16 18:49:32 PDT 2013
curl -V
curl 7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 OpenSSL/0.9.8y zlib/1.2.3 libidn/0.6.5
Protocols: tftp ftp telnet dict ldap ldaps http file https ftps
Features: IDN IPv6 Largefile NTLM SSL libz
Aaron