[4.0] Namespace JMailHelper

[brianteeman]

Fix the last remaining namespace update for JMailHelper

[alikon]

I have tested this item ✅ successfully on 3cb279e

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[Quy]

I have tested this item ✅ successfully on 3cb279e

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[Quy]

RTC

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[wilsonge]

Thanks!

[brianteeman]

thanks