Net block blocked

I work for an ISP which recently obtained a new network block from ARIN. The new IP addresses in that CIDR are not being recognized as IP addresses within the United States, or are being seen as over-seas IP addresses. This has resulted in the IP addresses to be blocked by several financial institutions, military agencies, VPN Gateways, PGP, etc. We are currently working on this issue on a case by case basis, but it is becoming an overwhelming task to try and track down the appropriate contact(s) of the larger organizations and military agencies. If anyone has some advise, suggestions, or assistance that they can offer in regards to this situation, it would be greatly appreciated. Thank you, J. Borris