It is possible to do this with OpenOffice, but not through OpenOffice::OODoc modules. These modules read and manipulate native OpenOffice formats, such as SXW and ODT, directly. They do not, however, include the code needed to import other formats (such as RTF, DOC, etc.) into OpenOffice formats.
You would be better served to look at OpenOffice macro programming, such as through OpenOffice Basic.