Round Robin in resolving the DOMAIN name

Hello!

We have an issue with resolving dns name or our domain, lets say, mycompany.com

In the domain there are around 100 sites, geographically spread. The DC\DNS servers are windows server 2003 r2, the clients are windows xp, DNS zones are active directory integrated, Round Robin, Netmask ordering are enabled.

The issue: when I ping mycompany.com from the XP clients the answer is everytime different DC\DNS server ip address. E.g.

H:\>ipconfig /flushdns

H:\>ping mydomain.com

Pinging mycompany.com [2.2.2.2] with 32 bytes of data:

and so on.

1.1.1.1, 2.2.2.2 servers may be quite far from the site of the client with huge latency

If I ping mycompany.com from the servers (W2K3 R2) the answer each time is the ip address of the DNS server which actually provides the answer(the "closest" DC\DNS to the server)

I assume that in the normal circumstances it should be like this:

1) DNS client sending a request to the closest DC\DNS server (the server in the same AD site) to resolve mycompany.com to ip address

2) The DNS server should answer with the ip of itself (and it actully does if I perform request from W2K3 servers)

Could you please advise the reason why DNS servers answer to clients with everytime different ip addresses? And how to fix it?