If you can't telnet to the port, then you certainly won't be able to use ASDM to control it. Is there any chance you are having a routing or internal firewall issue? That is, what's the network like between your admin machine and the ASA?
Some other questions/techniques to try:
Is it configured for administation over SSH?
Can you connect a serial cable to the console port, or connect through a remote console solution?
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
[toc:faq]Introduction:This document describes details on how NAT-T
works.Background:ESP encrypts all critical information, encapsulating
the entire inner TCP/UDP datagram within an ESP header. ESP is an IP
protocol in the same sense that TCP and UDP are I...