PVS-Studio warning V645 for ReactOS

void shell(int argc, const char *argv[])
{
  char CmdLine[MAX_PATH];
  ....
  strcpy( CmdLine, ShellCmd );

  if (argc > 1)
  {
    strncat(CmdLine, " /C", MAX_PATH);
  }

  for (i=1; i<argc; i++)
  {
    strncat(CmdLine, " ", MAX_PATH);
    strncat(CmdLine, argv[i], MAX_PATH);
  }
  ....
}

This suspicious code was found in ReactOS project by PVS-Studio static code analyzer.
Warning message is:
V645 The 'strncat' function call could lead to the 'CmdLine' buffer overflow. The bounds should not contain the size of the buffer, but a number of characters it can hold. cmds.c 1314

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/