Colliding password protected MS office 97-2003 documents

[childintime]

Hi, thank you for your work on office modules. I have problem with this hash:

$oldoffice$1*ab89af231e69e38ec4ab428f5aaac154*2c9f05787534bbfd34c833841851a172*c69788ef69df9700960fc02c55524438

i cant crack rc4 like described above, i run this (on 2x7970, latest oclhashcat from web):

./oclHashcat64.bin -m 9710 hash -a 3 -w 3 ?b?b?b?b?b -o hash.rc4

and result:

Session.Name...: oclHashcat
Status.........: Exhausted
Input.Mode.....: Mask (?b?b?b?b?b) [5]
Hash.Target....: $oldoffice$1*ab89af231e69e38ec4ab428f5aaac154*2c9f05787534bbfd34c833841851a172*c69788ef69df9700960fc02c55524438
Hash.Type......: MS Office <= 2003 MD5 + RC4, collision-mode #1
Time.Started...: Wed Oct 29 13:07:21 2014 (1 hour, 57 mins)
Time.Estimated.: 0 secs
Speed.GPU.#1...: 77880.4 kH/s
Speed.GPU.#2...: 78220.1 kH/s
Speed.GPU.#*...: 156.1 MH/s
Recovered......: 0/1 (0.00%) Digests, 0/1 (0.00%) Salts
Progress.......: 1099511627776/1099511627776 (100.00%)
Skipped........: 0/1099511627776 (0.00%)
Rejected.......: 0/1099511627776 (0.00%)
HWMon.GPU.#1...: 87% Util, 65c Temp, 80% Fan
HWMon.GPU.#2...: 89% Util, 61c Temp, 73% Fan

Started: Wed Oct 29 13:07:21 2014
Stopped: Wed Oct 29 15:04:27 2014

any suggestions?
i get hash from regular old office word document, using office2john.py utility.