Is GNU-Comm ready for "System Integrator"/ commercial installation?

Hello,

an old-hand PABX installation guy and myself (was a software guy) are
looking to provide IP Telephony solutions to our clients. VoIP is new to
both of us, all telephony is new to me personally (besides actually
_using_ phones, to state the obvious).

We have an existing client, which may "upgrade" (I hope) from existing
traditional PABX installation (due to be installed in two weeks), to
PC-based software/ hybrid setup, if we can put a quote together in the
next week and a half.

The client is actually two companies with one common executive (who, in
the current setup, would simply have two phone handsets - for access to
a line from each company's PABX). The companies are otherwise entirely
separate. They are moving to new premises, currently with a transfer of
the existing PABX equipment (have to get the make and model yet sorry).

The requirements:
 - two companies
 - 30 employees in one, 12 in the other (say 50 handsets to start)
 - potentially growing to double or triple over next few years
 - two permanent fax lines
 - one permanent security (POTS) line
 - requirement for two or more POTS lines for modems
 - ISDN (or similar) pipe to backbone provider, through which telephone
lines and internet connection come through
 - Based in Sydney, Australia.

What I need to figure out, so as to be able to put a proposal together:
 - hardware (cards, server, handsets)
 - software (PABX, voice mail, fax; OSS/Free Software vs. Proprietary)

If there is a better place to post such a question, please let me know.

I am happy to be pointed at reading material. In fact I'm just starting
out here wrt telephony stuff (was a programmer and software designer for
a few years, then technnical doco and management), although the other
guy has been installing traditional (proprietary I guess you'd call
them) PABXs for years.

Once we get a few VoIP clients, I imagine needing to contract for
customization and/ or features development. Ideally we can use Free
Software (including drivers) from day one (I see it as the most
efficient development model long term - spreading development cost over
all the users). Even if we have to start out with (some) proprietary
software, as soon as there is some revenue to speak of, I will be
directing this to OSS/FS solutions - I'm certain it's cheaper in the
long run for System Integrators/ Installers (like ourselves), and
therefore clients.

I've spent the recent weekend reading a bunch of bits on different
websites, including the gnucomm overview - although that appears to have
been last updated in 2000 or so... so getting a grasp of "the big
picture" is proving a little challenging for me at the moment.

Any help appreciated
Zenaan

-- 
Mr Zenaan Harkness
Mobile: +61 (0)412 166 990
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