Using eCAP to black\white\gray list clients?

[Eliezer Croitoru]

I am wondering about how to use eCAP to make some users understand that 
their IP is abusing the service..

In squid I can mark connections and some other stuff while the OS does 
the actuall limit.
I have tried to acutally read the eCAP examples etc but never understood 
how to really make use of it.
I know that there are docs but I am not starting reading them over again.

So what would be the best code implementation that would run this 
function?, Block\White\Gray list users by IP?
In ruby I can use very simple libraries and very clean code to implenent 
the DB on REDIS\TOKYOTYRANT\MEMCACHED etc.

Issues with eCAP:
- What aspect do I need to take about concurrent requests handling?
- Can I use standard libs for MYSQL or any other DB?
- what would you choose?

Please take in considiration that I know a bit c a bit c++ 8 bits of 
Ruby 1-2 bits of perl and snippets of py php and some others.

Thanks,
Eliezer