5. The system according to claim 4 , wherein the dynamic converter further comprises: a first replacement section for replacing each of a plurality of character string output instructions which have not been converted into the second buffering instructions, with a first buffering instruction for adding a character string, which is to be outputted, to the first buffer, without converting the character code set from the first code set; and an instruction insertion section for inserting a conversion instruction into a part of the output program executed before the second buffering instruction and after the plurality of first buffering instructions, the conversion instruction collectively converting a character code set of a plurality of character strings stored in the first buffer into the second code set, and then adding the converted character strings to the second buffer.
14. The system according to claim 5 , further comprising a redundancy elimination section, wherein the instruction insertion section inserts the conversion instruction into a part to be executed immediately before each of the second buffering instructions which have been generated by replacing the character string output instructions; and the redundancy elimination section eliminates conversion instructions except one to be executed first among the plurality of conversion instructions which are successively executed without including the first buffering instruction.