Table 1: The log of all analysed observations and exposure times.

Date	Mission	Instrument	(ks)
05/30/1999	BeppoSAX	MECS	47
		PDS	56
11/20/1999	BeppoSAX	MECS	15
		PDS	34
05/03/2000	BeppoSAX	MECS	46
		PDS	31
05/27/2001	BeppoSAX	MECS	61
		PDS	38
05/29/2001	XMM-Newton	EPIC-PN	30