May be I come too late?

Nevertheless, I would propose the following circuit:



Caution: Just saw, that I forgot to draw free wheeling diode for relais! (Will correct this later.)

Capacitors shown are minimum value. Capacitor across 470R resistor is not necessary. Diodes shall help, if lamp has some inductivity. 3k3 resistor across base emitter of BC557B helps, if output high voltage of port is a bit smaller than +5V.
3k3 resistor value is a bit small, but low ohmic relais (about < 250Ohm) need it. If relais coil is higher impedant, resistor can be increased, perhaps 10k plus 10k.

Good luck,
Kai