sorry noob question maybe, i cant seem to make a market place bid X.77 or any amount. what am i doing wrong, as i see bids that are in decimal bids :s

thanks for the help

this is what it tells me

"Sorry, the Market is unable to accept decimal bids for iron!"

and market
Market Advisor

Buy    Needed         Sell    In Stock
Image iron    8.01 gc    xxxx        12.00 gc    xxxx
Image octarine    13.00 gc    xxxx        14.00 gc    xxxx
Image food    0.21 gc    xxxxx        0.30 gc    xxxxx
Image endurium    7.00 gc    xxxx        12.00 gc    xxxx