Fix deadlock in ASIDownloadCache when server doesn't return any explicit expiration time

Closes gh-102 (Many thanks to LeeMatthewHiggins for catching this)

@@ -317,6 +317,7 @@ static NSString *permanentCacheFolder = @"PermanentStore";
 		}
 		
 		// No explicit expiration time sent by the server
+		[[self accessLock] unlock];
 		return NO;
 	}
 	

@@ -24,7 +24,7 @@
 #import "ASIDataCompressor.h"
 
 // Automatically set on build
-NSString *ASIHTTPRequestVersion = @"v1.8-4 2010-11-20";
+NSString *ASIHTTPRequestVersion = @"v1.8-10 2010-11-24";
 
 NSString* const NetworkRequestErrorDomain = @"ASIHTTPRequestErrorDomain";