From BiblePortal Wikipedia

Hastings' Dictionary of the Bible [1]

JAHZEIAH . One of four men who are mentioned as opposing (so RV [Note: Revised Version.] ) Ezra in the matter of the foreign wives (  Ezra 10:15 ). The AV [Note: Authorized Version.] regarded Jahzeiah and his companions as supporters of Ezra, rendering ‘were employed about this matter.’ This view is supported by LXX [Note: Septuagint.] , 1E  Esther 9:14 RVm [Note: Revised Version margin.]; but the Heb. phrase here found elsewhere (cf.   1 Chronicles 21:1 ,   2 Chronicles 20:23 ,   Daniel 11:14 ) expresses opposition .

Holman Bible Dictionary [2]

 Ezra 10:15Jahaziah

International Standard Bible Encyclopedia [3]

ja - zē´ya , ja´zē̇ - ya ( יחזיה , yaḥzeyāh , "Yah sees"): In   Ezra 10:15 , son of Tikvah, and a contemporary of Ezra. It is disputed whether he and Jonathan opposed or supported Ezra in the matter of prosecuting those who had married foreign wives = Ezekias, 1 Esdras 9:14, or Ezias. See Jonathan , 9.

Two translations of the Hebrew phrase ( עמד על־זאת , ‛āmadh ‛āl - zō'th ) are given: (1) "stood over this matter," i.e. supported Ezra; so the King James Version ("were employed in this matter"), and so Septuagint, 1 Esdras 9:14, the Revised Version margin. This is supported by 9:4, "Let now our princes be appointed for all the assembly," where the same phrase is found. (2) The Revised Version (British and American) "stood up against this matter," so Bdb , Gesenius, Bertheau, Stade. Both translations can be supported by parallels in Hebrew. The context is better suited by the former rendering.