This is a study of the drug perifosine in combination with Gemcitabine. Perifosine is an oral anti-cancer agent that has been used in more than 140 people, but has not been combined with other drugs before this study. The study is designed to determine the highest dose of perifosine that can be administered to people every day while they are on a Gemcitabine regimen, without severe or prolonged nausea, vomiting and diarrhea. This study starts with patients taking 50 mg/day and goes up to 150 mg/day. After the highest tolerable dose is found, we will add 10 more patients at that dose.