This happened when JRE was localized into pt_BR in 6u21 b02.

In other non-asian locales, the mnemonic keys are based on the localized button labels. In pt_BR, the mnemonic keys are the same as what in English, regardless what the localized labels are. For example, in Deployment_pt_BR.java.


        { "general.about.btn", "Sobre..." },
        { "general.about.btn.mnemonic", "VK_B" },

// Here, it's better to be VK_S rather than VK_B

{ "general.cache.view.text", "Exibir..." },
{ "general.cache.view.text.mnemonic", "VK_V"},

Charcter "V" is not in text "Exibir...", so the mnemonic key is missing on this button.

Basically, all the mnemonic keys should be decided based on the localized label, and other buttons on the same panel (to avoid confilict, if two or buttons have the same beginning character on the label).