a lot of people asked me in irc how to convert it so here you go:
is the only function that changed is CanPenetrate.

instead of static pmtrace_t* tr = (pmtrace_t*)0x02252DF0; we can just use a global storage

pmtrace_t pmtrace;

int CanPenetrate( float *start, float *end, int power )
{
/*static*/pmtrace_t* tr = (pmtrace_t*) &pmtrace;
float view[3];
float dir[3];

view[0] = end[0] - start[0];
view[1] = end[1] - start[1];
view[2] = end[2] - start[2];

float length = VectorLength(view);

dir[0] = view[0] / length;
dir[1] = view[1] / length;
dir[2] = view[2] / length;

float position[3];
position[0] = start[0];
position[1] = start[1];
position[2] = start[2];
tr->startsolid = true;

while( power )
{
if( !tr->startsolid )
power--;
tr = gEngfuncs.PM_TraceLine( position, end, PM_TRACELINE_PHYSENTSONLY, 2, -1);

if( tr->fraction==1.0f )
return 1;
if( tr->allsolid )
return 0;

position[0] = tr->endpos[0] + dir[0] * 8.0f;
position[1] = tr->endpos[1] + dir[1] * 8.0f;
position[2] = tr->endpos[2] + dir[2] * 8.0f;
}
return 0;
}

this version works for 1.5 and 1.6 the same as the old one.
Credits: LTFX GUY and GD.
This Tutorial may not be redistributed but linked to.