Since I first posted here I've learned more about my husband's Hokans ancestry from members of his family who are doing genealogical research. I have posted what we have learned so far at my genealogical webpage: http://pages.cthome.net/frenabee/id68.htm
I'm not sure how accurate it is as I don't know the sources, but I'm assuming most of the information was obtained at the Genealogical Society of Finland, http://www.genealogia.fi/indexe.htm
at the HisKi Church Records section because I did verify most of the information there.
There is some controvery in the family as to whether my husband's great-grandfather Anders Hendrik Klemets was from Sweden or Finland. His son was Henrik Leander Matson/Håkans, supposedly he took Matson as his name upon arriving in the U.S. with his mother Johanna Karolina Håkans (we don't know where Anders was at that time) and we don't know where he got the name Matson -- but he later changed it to Hokans.