Are you using my Lasermine plugin?
Then you only need to modify the following condition in lm_step_beambreak function.
PHP Code:
if (equali(className, ENT_CLASS_BREAKABLE) || equali(className, ENT_CLASS_LASER))
ex) if sentry gun classname is "sentrygun".
PHP Code:
if (equali(className, ENT_CLASS_BREAKABLE) || equali(className, ENT_CLASS_LASER) || equali(className, "sentrygun"))