interesting buying behaviour

I bought some NGF a few days ago after the Lehman hedge settlement, but after reading the reports in more detail I thought that there may be better value elsewhere due to the fairly high cash costs and need to pay back the 97$m. Also didn't seem to be going anywhere much today on a very goo=d gold day.
So I took the opportunity to sell my very small position back today.
Here's the sales after I placed my order of sell 25000 at 0.210 on commsec.

12:01:23 PM 0.210 5,700 1,197.00
12:01:21 PM 0.210 100 21.00 XT
12:00:09 PM 0.210 150 31.50 XT
11:59:21 AM 0.210 100 21.00 XT
11:58:26 AM 0.210 150 31.50 XT
11:57:35 AM 0.210 150 31.50 XT
11:56:50 AM 0.205 6,154 1,261.57
11:56:15 AM 0.210 150 31.50 XT
11:55:02 AM 0.210 14,500 3,045.00
11:54:59 AM 0.210 150 31.50 XT
11:54:11 AM 0.210 100 21.00 XT
11:53:21 AM 0.210 150 31.50 XT
11:52:15 AM 0.210 150 31.50 XT
11:52:05 AM 0.205 30,800 6,314.00
11:51:13 AM 0.210 150 31.50 XT
11:50:20 AM 0.210 150 31.50 XT
11:49:04 AM 0.210 150 31.50 XT
11:48:48 AM 0.205 6,422 1,316.51
11:47:58 AM 0.210 150 31.50 XT
11:47:00 AM 0.210 150 31.50 XT
11:45:42 AM 0.210 300 63.00 XT
11:44:55 AM 0.210 100 21.00 XT
11:43:50 AM 0.210 150 31.50 XT
11:42:40 AM 0.210 150 31.50 XT
11:41:51 AM 0.210 2,000 420.00

What was really interesting to me are the cross trades- seeming to indicate that commsec or a commsec account holder was running a computer trade buying NGF at 210.!!!!!

At about $20 a trade it doesn't make much sense to buy $30 lots.!!

Anyway trade got taken out as first part of a big buy order
at 12.01.23.
Does anyone have any ideas on what may be happening here.