Merge pull request #51 from DQNEO/feature/fix-adodb

Squashed commit of the following:

commit 1878777001a2ae01c6dfab8bff4338946dc272e1
Author: DQNEO <DQNEO@dqneo.jp>
Date:   Fri Mar 23 23:32:24 2012 +0900

    add comment

commit 46c05b8820ea64edb47d9a8720043336e33bdbe0
Author: DQNEO <DQNEO@dqneo.jp>
Date:   Fri Mar 23 23:25:31 2012 +0900

    use english for error message