A remark on Brans-Dicke cosmological dust solutions with negative omega

Analysing the Brans-Dicke solutions for the dust phase, we show that, for n egative values of omega, they contain scenarios that display an initial sub luminal expansion followed by an inflationary phase. This is due to a repul sive cosmic effect. We discuss these solutions with respect to the results of the observation of high redshift supernova as well as the age problem an d structure formation. We establish possible connections of these solutions with those emerging from string effective models.