Bilt-in Cisco VPN Client problem

Buit-in Cisco VPN client problem. Hello, some days ago I discovered interesting problem with Cisco built-in VPN client. At our main office we have Cisco 1811 with EasyVPN enabled to give access to file server our outside workers. This is a some detail ! crypto isakmp client configuration group vpn key ******* dns 192.168.10.91 domain domain.tld pool vpn_pool acl 102 netmask 255.255.255.240 ! access-list 102 permit ip 192.168.10.0 0.0.0.255 any ! ip local pool vpn_pool 192.168.11.1 192.168.11.14 ! ip dhcp pool dhcp_pool import all network 192.168.10.0 255.255.255.0 default-router 192.168.10.1 option 42 ip 192.168.10.3 domain-name domain.tld dns-server 192.168.10.91 lease 10 ! So, internal subnet 192.168.10.0/24 VPN pool 192.168.11.1/28 ACL 102 it is Split Tunnel to corporate LAN (to 192.168.10.0/24) Users can VPN & reach every thing they need, but they can not see each other in VPN subnet. For example they can not ping each other. I actually need it to make some necessary repair with they Macintosh FIrst time I thought it is routing related problem, but routing table looks good t1000:~ ap$ ifconfig utun1 utun1: flags=8051 mtu 1280 inet 192.168.11.13 --> 192.168.11.13 netmask 0xfffffff0 t1000:~ ap$ netstat -nr | grep 192.168.11 192.168.10 192.168.11.13 UGSc 11 11 utun1 192.168.11/28 192.168.11.13 UGSc 1 0 utun1 192.168.11.13 192.168.11.13 UH 15 21 utun1 But most important & strange for me that I can not ping my self! t1000:~ ap$ ping 192.168.11.13 PING 192.168.11.13 (192.168.11.13): 56 data bytes Request timeout for icmp_seq 0 Request timeout for icmp_seq 1 Request timeout for icmp_seq 2 Firewall is disabled. Then I go to PC with Windows XP, setup Cisco VPN client for windows & check everything I told before & all working very well. I can ping my self, I can reach neighbor in VPN subnet. Any idea?