TYPO3 Core

I have this statement in one of my extensions' ext_tables.sql:

CREATE TABLE tx_csloauth2_oauth_access_tokens (
  access_token varchar(40) NOT NULL,
  client_id varchar(80) NOT NULL,
  user_id varchar(255),
  expires timestamp NOT NULL,
  scope varchar(2000),

  CONSTRAINT access_token_pk PRIMARY KEY (access_token)
) ENGINE=InnoDB;

This crashes the install tool when comparing the database structure.