Cisco 1760-V and ATA 186 issues ...

Hi,

I am new to Cisco VoIP. I've been configuring to get VoIP working on 1760-V with 2FXO card. I do not configure SIP or H.323 yet. I connect the FXO port with the outlet from the PBX in my lab. I have assigned a POT dial-peer to use one of the FXO port and two voip dial-peers to use ATA 186 and Microsoft NetMeeting.

I've got the following problems:
# voip calls to ATA extensions works only for the first time. For any other times, the calls ring on both of the ATA's ports and never connected. The problem can be solved by power off/on. But it works only for the first call and the problem still persist.
# VoIP calls can be initiated from Microsoft Netmeeting. But it cannot accept incoming calls. Is it normal or what do I need to configure in the cisco config for microsoft netmeeting.
# Netmeeting can call to voip lines attached to FXS port or ATA but not to the other Microsoft Netmeeting computers using Cisco Gateway. Is it normal or what configs have to be done in Cisco.
# What protocol it is used when simply using Cisco Router as a gateway without configuring H.323 or SIP?
# What other softphone or application can be used instead of Microsoft Netmeeting to utilize Cisco Router as a gateway and initiate/receive voip calls without using SIP or H.323.

Thanks.