An oil leak at the spark plug area (spark plug tubes) can be caused by a failing valve cover sealing rubber and/or camshaft holder o-ring. The sealing rubber and o-ring will need to be replaced to address this issue.Google+
Car Problem Reports
Honda CRX Oil Leak at Spark Plug Area Due to Failing Valve Cover Sealing Rubber/Camshaft Holder O-Ring
Honda CRX Problem
Engine Affected: 1.5L 4 Cylinder
Average Mileage: 172,299 mi (147,898 mi - 209,000 mi)
Visitor, 1991 Honda CRX, 1.5L 4 Cylinder, 209,000 mi
I have had this problem twice in the past couple of years. It seems like this is inherent to CRX's.