a bit mask where each bit position,
according to its value, has a specific
meaning:
bit 0:
0 - digits only (0-9, *, # and +)
1 - alphabet set
bit 1:
0 - SMS default alphabet (GSM
character set)
1 - UCS2 alphabet
bit 2:
0 - character sets defined by bit 0
and bit 1 are enabled
1 - character sets defined by bit 0
and bit 1 are disabled and the
"Yes/No" response is requested
bits 3-6:
0