asterisk users - Feb 2005 - CODEC declarations in IAX.conf

Hi:

I'm a bit confused about CODEC declarations in IAX.conf.

In the [GENERAL] section, should I declare NO codecs and no 
[allow|disallow all] statements in favor of declaring all CODEC rules 
within each context section?

If this is the case, I'm wondering then what exactly should remain in 
the general context... should it be only PORT bindings and TOS flags?

Thanks in advance,
/rg