For installation OpenVPN on PDA Windows Mobile 5,6,6.1, you need:

1. Install the program distribution kit in PDA on a flash card

2. With ActiveSync use this http://ovpnppc.ziggurat29.com/files/2.1.0/ovpnppcinst.en.exe or use cab file (it is necessary to copy cab file to memory of a handheld computer and to start installation there from – double clicks on cab to a file) http://ovpnppc.ziggurat29.com/files/2.1.0/ovpnppc.en.ARM.CAB

3. Download the configuration files VPN, which you received from technical support, and to unpack them in a folder \\Program Files \\Openvpn \\config on a PDA. Config should looks like:
client
dev tun
resolv-retry infinite
nobind
comp-lzo
verb 3
redirect-gateway
proto udp
remote server port
auth-user-pass
<ca>
</ca>  

4. For start OpenVPN you need to click on icon on bottom

5. Choose Start From Config – and select config - in our case, name of configuration file is 'config'