15. A system comprising: a processor; and a memory storing instructions that, when executed by the processor, cause the processor to perform operations comprising receiving, from a short message entity, a first message comprising a payload encoded in accordance with a first character encoding scheme and indicating a second character encoding scheme, wherein the first character encoding scheme comprises an extensible markup language encoding scheme, determining whether the second character encoding scheme comprises a reserved value, in response to determining that the second character encoding scheme comprises the reserved value, copying the first message byte-for-byte, and in response to determining that the second character encoding scheme comprises a short message peer-to-peer data coding scheme instead of the reserved value, transforming the payload of the first message from the extensible markup language encoding scheme to the short message peer-to-peer data coding scheme, wherein transforming the payload of the first message from the extensible markup language encoding scheme to the short message peer-to-peer data coding scheme comprises using a mapping table stored at the system to map the payload encoded in accordance with the extensible markup language encoding scheme to the short message peer-to-peer data coding scheme, the mapping table comprising extensible markup language encoding declarations, each of which is mapped to a respective short message peer-to-peer data encoding mapping.
15. A system comprising: a processor; and a memory storing instructions that, when executed by the processor, cause the processor to perform operations comprising receiving, from a short message entity, a first message comprising a payload encoded in accordance with a first character encoding scheme and indicating a second character encoding scheme, wherein the first character encoding scheme comprises an extensible markup language encoding scheme, determining whether the second character encoding scheme comprises a reserved value, in response to determining that the second character encoding scheme comprises the reserved value, copying the first message byte-for-byte, and in response to determining that the second character encoding scheme comprises a short message peer-to-peer data coding scheme instead of the reserved value, transforming the payload of the first message from the extensible markup language encoding scheme to the short message peer-to-peer data coding scheme, wherein transforming the payload of the first message from the extensible markup language encoding scheme to the short message peer-to-peer data coding scheme comprises using a mapping table stored at the system to map the payload encoded in accordance with the extensible markup language encoding scheme to the short message peer-to-peer data coding scheme, the mapping table comprising extensible markup language encoding declarations, each of which is mapped to a respective short message peer-to-peer data encoding mapping. 16. The system of claim 15 , wherein: the first message is of a first type; the payload is a first payload; and the operations further comprise generating a second message being of a second type and comprising a second payload encoded according to the second character encoding scheme.