rfc2317 - testing ISP setup?

[billd]

Hi,

I'm trying to get my ISP to allow me to reverse map
my own DNS for my small home network...  I had
some difficulty persuading them, however in the end
they said they did what needs doing...  I have set
everything up on my end as per the RFC2317 but
it still doesn't work and as far as I can tell, requests
are not being forwarded to my name server.  Is there any
way that I can check that they have done things
correctly as  it isn't working...  the vitals are:

my network address space is:

213.253.143.224 and netmask of 255.255.255.224

Their name server is

193.243.233.10

I am trying to figure out how dig works... but learning
very slowly... I'd appreciate if someone could tell me
a dig statement that would show me who's server would
be looked up for reverse DNS for this network space...
...

thanks
Bill