IPSEC between PIX 6.3 and asa 5520

Hi folks,
A pix 6.3 failed at a remote site so we placed a new one there.  It had a IPSEC to our main data center.

I rebuilt the pix but cant get the ipsec to come up, everything else works in terms of access to the internet:

access-list inside_nat0_outbound extended permit ip 10.50.28.0 255.255.255.0 205.132.168.0 255.255.255.0
access-list outside_cryptomap_20 extended permit ip 10.50.28.0 255.255.255.0 205.132.168.0 255.255.255.0
nat (inside) 0 access-list inside_nat0_outbound
crypto ipsec transform-set slcSet esp-3des esp-md5-hmac

sysopt connection permit-IPSec
crypto map outside_map 1 IPSec-isakmp
crypto map outside_map 1 match address outside_cryptomap_20
crypto map outside_map 1 set peer aa.aa.aa.aa
crypto map outside map 1 set transform-set slcSet
 
crypto map slcSet interface outside
isakmp enable outside
isakmp key something address aa.aa.aa.aa netmask 255.255.255.255

isakmp identity address

isakmp policy 1 authentication pre-share
isakmp policy 1 encryption 3des
isakmp policy 1 hash md5
isakmp policy 1 group 2
isakmp policy 1 lifetime 86400
isakmp policy 2 authentication pre-share
isakmp policy 2 encryption 3des
isakmp policy 2 hash sha
isakmp policy 2 group 2
isakmp policy 2 lifetime 86400

any help would be appreciated.