Communication 5.2 : truncate UUI via vectoring

[Alexandre Pawlowski]

Hello Guys,

I'm currently trying to find a way to reduce the length of the asaiuui within a vector.

A provider runs an IVR which routes calls to our Avaya PABX and send UUI data holding the customer ID and the VDN to route the call to.

The UUI data is a 16 caracter string which looks like this "9MAB123456785777".
The first two digits is the VDN encoded via the decimal values of the ASCII caracter (ie: '9' -> 57)
The next two digits is a constant
The next 8 digits is the customer ID.
The last four digits is the VDN to route the call to in plain ASCII caracters

I've set up a vector to check if the VDN is in a list of allowed VDNs, then check if there is a client ID.
I copy the VDN into the digits variable, then I copy the client ID at the beginning of the UUI field.
All is going well at this point. But I want to truncate the asaii UUI field from 16 digits to 8 digits.

I've tried something like this:
Variable O : asai uui Length 4 / Start 13 (VDN)
Variable N : asai uui Length 8 / Start 5 (Client ID)
Variable V : asai uui Length 8 / Start 1 (UUI first 8 digits)
Variable W : asai uui Length 8 / Start 9 (UUI next 8 digits)
[sup]
02 goto step 11 if O = none
03 goto step 11 if N = none
04 goto step 11 if O not-in table 4
05 set digits = none CATR O
06 set V = none CATR N
07 set W = none SEL 8
08
09
10 route-to digits with coverage n
11 busy
12 disconnect after announcement none
13 stop
[/sup]
But when I trace the vector it turns out line 7 doesn't truncate the UUI field but fills up the last 8 digits with 0
[sub]
10:45:56 0 0 ENTERING TRACE cid 1615
10:45:56 600 1 vdn e7906 bsr appl 0 strategy 1st-found override y
10:45:56 600 1 set P = none CATR 0000236982575777
10:45:56 600 1 operand = []
10:45:56 600 1 operand = [0000236982575777]
10:45:56 600 1 ========= CATR =========
10:45:56 600 1 variable P = [0000236982575777] asaiuui local
10:45:56 600 1 asaiuui chg from [] to [0000236982575777]
10:45:56 600 2 route-to number 7904 cov n if unconditionally
10:45:56 600 3 LEAVING VECTOR PROCESSING cid 1615
10:45:56 598 1 vdn e7904 bsr appl 0 strategy 1st-found override y
10:45:56 598 1 <blank>
10:45:56 598 2 goto step 11 if O = none
10:45:56 598 2 variable O = [5777] asaiuui local
10:45:56 598 3 goto step 11 if N = none
10:45:56 598 3 variable N = [23698257] asaiuui local
10:45:56 598 4 goto step 11 if O not-in table 4
10:45:56 598 4 variable O = [5777] asaiuui local
10:45:56 598 5 set digits = none CATR O
10:45:56 598 5 operand = []
10:45:56 598 5 variable O = [5777] asaiuui local
10:45:56 598 5 ========= CATR =========
10:45:56 598 5 digits = [5777]
10:45:56 598 6 set V = none CATR N
10:45:56 598 6 operand = []
10:45:56 598 6 variable N = [23698257] asaiuui local
10:45:56 598 6 ========= CATR =========
10:45:56 598 6 variable V = [23698257] asaiuui local
10:45:56 598 6 asaiuui chg from [00002369] to [23698257]
10:45:56 598 7 set W = none SEL 8
10:45:56 598 7 operand = []
10:45:56 598 7 operand = [8]
10:45:56 598 7 ========= SEL =========
10:45:56 598 7 variable W = [00000000] asaiuui local
10:45:56 598 7 asaiuui chg from [82575777] to [00000000]
10:45:56 598 8 queue-to
10:45:56 598 8 queueing to skill 49 pri m
10:45:56 598 8 Local Agent Preference=n
10:45:56 598 8 Agent Login ID: 5001 Logged in at station: 2660
10:45:56 598 8 LEAVING VECTOR PROCESSING cid 1615
10:45:56 598 8 TRACE COMPLETE cid 1615
[/sub]
Is there any way I can truncate the UUI field within a vector? I've looked up the Avaya vector programming guide but that wasn't very helpful.
I know I can do this with an adjunct but I want to keep things as simple as possible.

Thanks for your insights !