Using Fraction Traded Smaller Than 1/100000000

[gwgreen at cox.net]

I am trying to match my account with the accuracy of the fraction traded for a fund that trades in fractions of 1/1000000000, however I can't seem to decrease the fraction traded for this commodity below 1/100000000 (the up arrow is grayed out when I reach 1/100000000),  Is there a way to make the fraction traded smaller?

e.g. The account shows 15.12345678 shares, but I need 15.123456789 shares.

Searching on the list gave me a clue about making sure that the account is set to use the commodity value, and I made sure I am set up this way.

Garrett