-(defalias 'mail-header-parse-content-type 'rfc2231-parse-string)
-(defalias 'mail-header-parse-content-disposition 'rfc2231-parse-string)
+(defalias 'mail-header-parse-content-type 'rfc2231-parse-qp-string)
+(defalias 'mail-header-parse-content-disposition 'rfc2231-parse-qp-string)