Add the following three lines,
#define memcpy memcpyLMM
#define memset memsetLMM
#define memset memcmpLMM
into the line#19 (right next to cstrlen) of this file:
LMM stands for Large Memory Model.
As the memcpyLMM function was not defined, it is not possible to copy strings of size more than 255 because it has to be copied between different pages itself. So adding the function definition will solve the problem.