Судя по комментам Вовголовы, оружие должно быть хотя бы ilvl 30+
https://ru.wowhead.com/item=3829/%D0...glish-comments
на это указывает не один коммент (которые, заметьте, не заминусованы и не удалены).

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The Oil might also require a weapon of the same level (30+), As I tried to apply it to my level 22 Reef Axe when I dinged 30, It stated that the target level was too low
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Тут он малёха прогнал, упомянув clvl 22 для этой шмотки, хотя масло смотрело явно на ilvl 27.

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If you're under level 30, but you have a weapon with an item level of 30 or higher you can have a someone else level 30 or higher put Frost Oil on your weapon through the trade window.

19 twinks, Runic Darkblade, Gutterblade, Glacial Stone and Seraph's Strike are the only weapons available to you that can take this.

Edit: As of patch 4.0.3, these weapons have been grandfathered and are no longer obtainable at 19.
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