Index: src/OFApplication.m
==================================================================
--- src/OFApplication.m
+++ src/OFApplication.m
@@ -35,10 +35,11 @@
 #import "OFNotificationCenter.h"
 #import "OFPair.h"
 #import "OFRunLoop+Private.h"
 #import "OFRunLoop.h"
 #import "OFSandbox.h"
+#import "OFStdIOStream.h"
 #import "OFString.h"
 #import "OFSystemInfo.h"
 #import "OFThread+Private.h"
 #import "OFThread.h"
 
@@ -258,13 +259,12 @@
 					continue;
 				}
 
 				pos = [tmp rangeOfString: @"="].location;
 				if (pos == OFNotFound) {
-					fprintf(stderr,
-					    "Warning: Invalid environment "
-					    "variable: %s\n", tmp.UTF8String);
+					OFLog(@"Warning: Invalid environment "
+					    "variable: %@", tmp);
 					continue;
 				}
 
 				key = [tmp substringToIndex: pos];
 				value = [tmp substringFromIndex: pos + 1];
@@ -300,13 +300,12 @@
 					continue;
 				}
 
 				pos = [tmp rangeOfString: @"="].location;
 				if (pos == OFNotFound) {
-					fprintf(stderr,
-					    "Warning: Invalid environment "
-					    "variable: %s\n", tmp.UTF8String);
+					OFLog(@"Warning: Invalid environment "
+					    "variable: %@", tmp);
 					continue;
 				}
 
 				key = [tmp substringToIndex: pos];
 				value = [tmp substringFromIndex: pos + 1];
@@ -394,12 +393,12 @@
 				void *pool = objc_autoreleasePoolPush();
 				OFString *key, *value;
 				char *sep;
 
 				if ((sep = strchr(*env, '=')) == NULL) {
-					fprintf(stderr, "Warning: Invalid "
-					    "environment variable: %s\n", *env);
+					OFLog(@"Warning: Invalid environment "
+					    "variable: %s", *env);
 					continue;
 				}
 
 				key = [OFString
 				    stringWithCString: *env

Index: src/OFObject.m
==================================================================
--- src/OFObject.m
+++ src/OFObject.m
@@ -39,10 +39,11 @@
 #import "OFMethodSignature.h"
 #import "OFRunLoop.h"
 #if !defined(OF_HAVE_ATOMIC_OPS) && defined(OF_HAVE_THREADS)
 # import "OFPlainMutex.h"	/* For OFSpinlock */
 #endif
+#import "OFStdIOStream.h"
 #import "OFString.h"
 #import "OFThread.h"
 #import "OFTimer.h"
 #import "OFValue.h"
 
@@ -250,17 +251,16 @@
 
 #if !defined(OF_APPLE_RUNTIME) || defined(__OBJC2__)
 static void
 uncaughtExceptionHandler(id exception)
 {
-	OFString *description = [exception description];
 	OFArray OF_GENERIC(OFValue *) *stackTraceAddresses = nil;
 	OFArray OF_GENERIC(OFString *) *stackTraceSymbols = nil;
 	OFStringEncoding encoding = [OFLocale encoding];
 
-	fprintf(stderr, "\nRuntime error: Unhandled exception:\n%s\n",
-	    [description cStringWithEncoding: encoding]);
+	OFLog(@"Runtime error: Unhandled exception:");
+	OFLog(@"%@", exception);
 
 	if ([exception respondsToSelector: @selector(stackTraceAddresses)])
 		stackTraceAddresses = [exception stackTraceAddresses];
 
 	if (stackTraceAddresses != nil) {
@@ -271,32 +271,31 @@
 			stackTraceSymbols = [exception stackTraceSymbols];
 
 		if (stackTraceSymbols.count != count)
 			stackTraceSymbols = nil;
 
-		fputs("\nStack trace:\n", stderr);
+		OFLog(@"");
+		OFLog(@"Stack trace:");
 
 		if (stackTraceSymbols != nil) {
 			for (size_t i = 0; i < count; i++) {
 				void *address = [[stackTraceAddresses
 				    objectAtIndex: i] pointerValue];
 				const char *symbol = [[stackTraceSymbols
 				    objectAtIndex: i]
 				    cStringWithEncoding: encoding];
 
-				fprintf(stderr, "  %p  %s\n", address, symbol);
+				OFLog(@"  %p  %s", address, symbol);
 			}
 		} else {
 			for (size_t i = 0; i < count; i++) {
 				void *address = [[stackTraceAddresses
 				    objectAtIndex: i] pointerValue];
 
-				fprintf(stderr, "  %p\n", address);
+				OFLog(@"  %p", address);
 			}
 		}
-
-		fputs("\n", stderr);
 	}
 
 	abort();
 }
 #endif