I developed a web application and host it in window 2000 using iis, but the web is not working properly, once awhile this error message prompt out.

Microsoft OLE DB Provider for ODBC Drivers (0x80040E4D)[Informix][Informi... ODBC Driver][Informix]Attempt to connect to database server (infimacs2) failed.

i'm using ODBC for database connection,and my informix driver version is "INFORMIX 3.81 32 BIT".