diff --git a/lib/defs.js b/lib/defs.js
index a0ab0f1..976ea08 100644
--- a/lib/defs.js
+++ b/lib/defs.js
@@ -193,6 +193,10 @@ types = {
 			return buffer.toString('ascii', offset, offset + length);
 		},
 		write: function(value, buffer, offset) {
+			if (typeof value === 'number') {
+				value = value.toString();
+			}
+
 			if (typeof value === 'string') {
 				value = new Buffer(value, 'ascii');
 			}
@@ -200,6 +204,10 @@ types = {
 			buffer[offset + value.length] = 0;
 		},
 		size: function(value) {
+			if (typeof value === 'number') {
+				value = value.toString();
+			}
+
 			return value.length + 1;
 		},
 		default: ''