CDR data

Hi there,
I’m using Asterisk 1.4 and Freepbx 2.4.0.0. When i’m looking through the CDR, there are some records I cannot understand the meaning of it.
There are mainly two type of records which i cannot understand.

  1. First one shows, LastApp and Destination as “busy”, LastData as “20”, Disposition as “Answered” and Duration is a non-zero value.
  2. The second problem is in some records destination shows as “s”.
    Here are some some sample records.

13/06/2008 08:32 SIP/xxx.xxx.xxx.xxx-bc362f60 1823271xxx “01823271xxx” <01823271xxx> Busy 20 busy ANSWERED 11
13/06/2008 08:34 SIP/xxx.xxx.xxx.xxx-b80444e0 1460533xxx “01460533xxx” <01460533xxx> Busy 20 busy ANSWERED 3
13/06/2008 08:06 SIP/4006-008661d0 4011 4011 s ANSWERED 840
13/06/2008 08:45 SIP/3942-00893640 3911 3911 s ANSWERED 186

Could anyone please explain to me what these mean?