the spec version is 3.0

Signed-off-by: Lukas Jungmann <lukas.jungmann@oracle.com>
diff --git a/spec/src/main/asciidoc/ch07-customize_xml_schema.adoc b/spec/src/main/asciidoc/ch07-customize_xml_schema.adoc
index 60eed3d..c3b5947 100644
--- a/spec/src/main/asciidoc/ch07-customize_xml_schema.adoc
+++ b/spec/src/main/asciidoc/ch07-customize_xml_schema.adoc
@@ -167,7 +167,7 @@
 binding declarations. For example, a future version of this
 specification may use the version attribute to specify backward
 compatibility. To indicate this version of the specification, the
-`version should` be `"2.0"`. It is also valid for @version to be “1.0”.
+`version should` be `"3.0"`. It is also valid for @version to be “1.0”.
 If any other version is specified, it must result in an invalid
 customization as specified in link:jaxb.html#a1544[See Invalid
 Customizations].”
@@ -198,7 +198,7 @@
 +
 [source,xml,indent=4]
 ----
- <jaxb:bindings jaxb:version="2.0" ... />
+ <jaxb:bindings jaxb:version="3.0" ... />
 ----
 +
 Specification of both `version` and