Is there evidence of a Buddhist influence on Greek Stoicism?

Stoic philosophy seems to share a lot with Buddhist wisdom. Since Zeno of Citium (generally credited as the founder of Stoicism) is said to have lived a couple hundred years after Siddhartha Gautama, it seems possible that some cross pollination of ideas may have influenced the development of Stoic philosphy. Is there any evidence (other than the similarities in philosophy) that this happened?