DBCS OS/2 is a common name of the OS/2 NLVs (National Language Version) that IBM provides to the far east Asia countries which require the DBCS character set for their own national languages.
IBM provides the following NLS DBCS OS/2 editions
The original SBCS OS/2 is enhanced to support the DBCS functions in Japan. The first DBCS version of OS/2 is the Japanese OS/2. Like the SBCS OS/2, the OS/2 J versions have been shipped; SE J1.0 1.1 1.2 1.3; EE J1.0 1.1 1.2 1.3 and OS/2 J2.0 J2.1.
The OS/2 NLS version for Korea is called Hangeul OS/2. It is enhanced from the OS/2 J. It shares the DBCS features of the OS/2 J and enhances other NLS and country unique features for the Korean customers. OS/2 H versions have been shipped; SE H1.0 1.2 1.3; EE H1.0 1.2 1.3 and OS/2 H2.0 H2.1.
The OS/2 NLS version for the P.R.C. is called OS/2 P. It supports the Simplified Chinese character set, so also called OS/2 S-Chinese version. It shares the common DBCS features and has its own NLS and country unique features. The OS/2 P is provided from version 2.1 and supports the combined code page 1381, known as GB code.
The OS/2 NLS version for Taiwan, is called Traditional Chinese OS/2. It shares the common DBCS features and has its own NLS and country unique features. OS/2 T versions have been shipped; SE T1.0 1.2 1.3; EE T1.0 1.2 1.3 and OS/2 T2.0 T2.1.