The problem is best illustrated by the following picture sourcetree.png
So we started with a common base, commit id 81109ae, then I did some change and my colleague did some change too. Then he merged my codes and continued with his work (commit 97cfed3). I continued to work on my own too (4103044).
Then I merged his code and have all of the latest code (commit a78cfd3) So far so good. I can see what changes were introduced in this commit.
Then my colleague merged the latest code as well. His codes were also updated the latest codes. BUT sourcetree added just a label to that commit indicating his codes were also updated too. He can not see what changes were introduced into his branch, to be exact in his case, he can not see what I did commit 4103044 that merged into his codes base.
So is this a sourcetree problem or git ?
Thanks!