Here is the TCPdump when i try to connect to the VNC Server.
01:03:19.260239 IP PG004.lan.56417 > 172.21.13.153.5900: Flags [S], seq 961657843, win 8192, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
01:03:19.260239 IP PG004.lan.56417 > 172.21.13.153.5900: Flags [S], seq 961657843, win 8192, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
01:03:19.260530 IP 172.21.13.153.5900 > PG004.lan.56417: Flags [R.], seq 0, ack 961657844, win 0, length 0
01:03:19.260560 IP 172.21.13.153.5900 > PG004.lan.56417: Flags [R.], seq 0, ack 1, win 0, length 0
01:03:19.763959 IP PG004.lan.56417 > 172.21.13.153.5900: Flags [S], seq 961657843, win 8192, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
01:03:19.763959 IP PG004.lan.56417 > 172.21.13.153.5900: Flags [S], seq 961657843, win 8192, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
01:03:19.764249 IP 172.21.13.153.5900 > PG004.lan.56417: Flags [R.], seq 0, ack 1, win 0, length 0
01:03:19.764278 IP 172.21.13.153.5900 > PG004.lan.56417: Flags [R.], seq 0, ack 1, win 0, length 0
01:03:20.267022 IP PG004.lan.56417 > 172.21.13.153.5900: Flags [S], seq 961657843, win 8192, options [mss 1460,nop,nop,sackOK], length 0
01:03:20.267022 IP PG004.lan.56417 > 172.21.13.153.5900: Flags [S], seq 961657843, win 8192, options [mss 1460,nop,nop,sackOK], length 0
01:03:20.267283 IP 172.21.13.153.5900 > PG004.lan.56417: Flags [R.], seq 0, ack 1, win 0, length 0
01:03:20.267311 IP 172.21.13.153.5900 > PG004.lan.56417: Flags [R.], seq 0, ack 1, win 0, length 0