Index: src/OFString.m
==================================================================
--- src/OFString.m
+++ src/OFString.m
@@ -974,11 +974,11 @@
 - (intmax_t)decimalValue
 {
 	int i = 0;
 	intmax_t num = 0;
 
-	if (string[0] == '-')
+	if (string[0] == '-' || string[0] == '+')
 		i++;
 
 	for (; i < length; i++) {
 		if (string[i] >= '0' && string[i] <= '9') {
 			if (INTMAX_MAX / 10 < num ||

Index: tests/OFStringTests.m
==================================================================
--- tests/OFStringTests.m
+++ tests/OFStringTests.m
@@ -226,10 +226,11 @@
 	    [[a objectAtIndex: i++] isEqual: @""] &&
 	    [[a objectAtIndex: i++] isEqual: @""])
 
 	TEST(@"-[decimalValue]",
 	    [@"1234" decimalValue] == 1234 &&
+	    [@"+123" decimalValue] == 123 &&
 	    [@"-500" decimalValue] == -500 &&
 	    [@"" decimalValue] == 0)
 
 	TEST(@"-[hexadecimalValue]",
 	    [@"123f" hexadecimalValue] == 0x123f &&