SAP Adapter crashes

Has anyone experienced cases where the SAP Adapter is crashing?? I get these entries in our dev_rfc.trc file

**** ERROR file opened at 20040429 085047 Eastern Dayligh, SAP-REL 620,0,941 RFC-VER 3 583708 MT-SL

**** ERROR file opened at 20040429 085047 Eastern Dayligh, SAP-REL 620,0,941 RFC-VER 3 583708 MT-SL

**** ERROR file opened at 20040429 085047 Eastern Dayligh, SAP-REL 620,0,941 RFC-VER 3 583708 MT-SL

**** ERROR file opened at 20040429 085047 Eastern Dayligh, SAP-REL 620,0,941 RFC-VER 3 583708 MT-SL

**** ERROR file opened at 20040429 085047 Eastern Dayligh, SAP-REL 620,0,941 RFC-VER 3 583708 MT-SL

**** ERROR file opened at 20040429 085047 Eastern Dayligh, SAP-REL 620,0,941 RFC-VER 3 583708 MT-SL

**** ERROR file opened at 20040429 085047 Eastern Dayligh, SAP-REL 620,0,941 RFC-VER 3 583708 MT-SL

They correspond exactly to when IS either hangs or crashes completely. I’m wondering what can cause this and what the remedy is if any.