It sounds like you have a BlackJack II if the space and sym are the same button.
According to the user manual, hold down the space button to get the the symbol grid.
Short press inserts a space.
Press and hold to display the symbols grid.
http://www.samsung.com/us/support/detail/supportPrdDetail.do?menu=SP00&prd_ia_cd=01010100&prd_mdl_cd=SGH-I617TIAATT&prd_mdl_name=SGH-I617&prd_ia_sub_class_cd=P