diff --git a/reactos/base/services/dhcp/compat.c b/reactos/base/services/dhcp/compat.c
index ec132ca360a..83c9c12ea8c 100644
--- a/reactos/base/services/dhcp/compat.c
+++ b/reactos/base/services/dhcp/compat.c
@@ -32,11 +32,36 @@ u_int32_t arc4random()
 
 
 int inet_aton(const char *cp, struct in_addr *inp)
+/* inet_addr code from ROS, slightly modified. */
 {
-	inp->S_un.S_addr = inet_addr(cp);
-	if (INADDR_NONE == inp->S_un.S_addr)
+	ULONG Octets[4] = {0,0,0,0};
+	ULONG i = 0;
+
+	if(!cp)
 		return 0;
 
+	while(*cp)
+	{
+		CHAR c = *cp;
+		cp++;
+
+		if(c == '.')
+		{
+			i++;
+			continue;
+		}
+
+		if(c < '0' || c > '9')
+			return 0;
+
+		Octets[i] *= 10;
+		Octets[i] += (c - '0');
+
+		if(Octets[i] > 255)
+			return 0;
+		}
+
+	inp->S_un.S_addr = (Octets[3] << 24) + (Octets[2] << 16) + (Octets[1] << 8) + Octets[0];
 	return 1;
 }