an old one but if you are still online the HBC records are housed in Winnipeg...and he was in service for any length of time there are records of his work. His servants papers may reveal more about his date of birth and actual place of birth to be certain you are looking at the right person.
They also have mini bios of some servants, a son of John James is a sample here:
http://www.gov.mb.ca/chc/archives/hbca/biographical/s/smith_james1864-1871.pdfah, here is his file: so you had proper dates
SMITH, John James b.1791- d.1850 Westminster, London ENTERED SERVICE: 1808 1808 To Albany on Prince of Wales
children are named for both marriages...
http://www.gov.mb.ca/chc/archives/hbca/biographical/s/smith_john-james.pdfThis site says was first married to a "country wife" ( aboriginal woman, married out of the church in the ways of the country which can end at any time one chooses before the birth of a child, but for many it was self-extended beyond that restriction...

)
Then married Nancy FAVEL Abt. 1834 in Red River District
The site says He was born 1791 in Westminster, England, where he entered the service of the Hudson's Bay Company (in the position of School Master) and sailed to Canada from Gravesend Port, and died October 15, 1850 in St Andrew's Parish District, Red River Settlement (Manitoba).
http://archiver.rootsweb.ancestry.com/th/read/METISGEN/2002-09/1031985610this site says he was born 1798 & his parents were: William Hart Smith and Hannah Woodman but you'd have to check their sources as the wrong birth date puts their research off on a bad leg......
http://familytreemaker.genealogy.com/users/s/m/i/Carol-Smith-24/WEBSITE-0001/UHP-0608.htmlThey also name a brother for him...there is an HBC file of the same name, but it doesn't state on either biothat they were brothers...so interested where they found this information...as they seem to have hung their hats on any hook found...