Help with MySQL_Proxy iApp

I've made some progress on this. I discovered one of the binary scans statements was selected a starting character that came after the user info of the MySQL payload.

I was able to get the client connection working by changing this line from the below

binary scan $clientside_mysql_arg @31A* from_client_user_payload

to this

binary scan $clientside_mysql_arg @4A* from_client_user_payload

Unfortunately, I fixed one problem only to find another. The iRule is not completing the three-way handshake with the actual DB server. It sends the initial syn, the DB servers replies with a syn ack, and then nothing. The F5 never responds to the syn ack and the DB server retransmists the syn ack.

The iRule is erroring out at the "TCP::respond [eval $client_auth_packet]" statement in this section of the iRule.

 when SERVER_DATA {
    if { $authenticated_state($serverside_current_pool) != 1 } {
            log local0.debug "BIG-IP MySQL Proxy -- serverside authenticated flag not set"
            set serverside_payload [TCP::payload]
            binary scan $serverside_payload c3cH2a* serverside_mysql_len serverside_mysql_num serverside_mysql_cmd serverside_mysql_arg

            if { $serverside_mysql_num == 0 && $serverside_mysql_cmd eq "0a" } {
                    log local0.debug "BIG-IP MySQL Proxy -- mysql server: received WELCOME packet"
                    binary scan [findstr $serverside_mysql_arg "\000" 2] i1a8x1B16c1B16x13a12x1 welcome_thread_id welcome_scramble_buff1 welcome_capabilities welcome_language welcome_status welcome_scramble_buff2

                    set welcome_hash_stage $welcome_scramble_buff1
                    append welcome_hash_stage $welcome_scramble_buff2 [sha1 [binary format H40 [class lookup $from_client_user mcom-db-qa.app_data_group]]]
                    binary scan [binary format H40 [class lookup $from_client_user mcom-db-qa.app_data_group]] c* welcome_xor_lhs
                    binary scan [sha1 $welcome_hash_stage] c* welcome_xor_rhs
                    set welcome_xor_buffer [list]
                    foreach l $welcome_xor_lhs r $welcome_xor_rhs {
                            lappend welcome_xor_buffer [expr { $l ^ $r }]
                    }

                     http://forge.mysql.com/wiki/MySQL_Internals_ClientServer_Protocol
                    log local0.debug "BIG-IP MySQL Proxy -- serverside responding with client AUTH packet"
                    set client_auth_formatting "B16B16i1c1x23A*x1c1c*A*x1"
                    set client_auth_args [list]
                    lappend client_auth_args 1000111110100010 0000001000000000 1073741824 48 $from_client_user 20 $welcome_xor_buffer $from_client_database
                    set client_auth_length [string length [eval "binary format $client_auth_formatting $client_auth_args"]]
                    set client_auth_packet "binary format s1x1c1$client_auth_formatting $client_auth_length 1 $client_auth_args"

                    TCP::respond [eval $client_auth_packet]
                    TCP::payload replace 0 [TCP::payload length] ""
                    TCP::collect
            }