Do Receivable activities (adjustments) generates gain/loss journal entries?

We have a primary ledger in UYU (Uruguayan Pesos)

1) Created an invoice with 122 USD amount, Tax Rate Type=Corporate, Tax Rate Date=28-MAY-2017 Rate=24.2213, it will be converted to 2955 UYU (122*24.2213).

2) Create an adjustment on 29-MAY-2017 for -61 Tax Rate Type=Corporate, Tax Rate Date=29-MAY-2017 Rate=28.2213, is should be converted to 1721,5 UYU (61*28.2213)

3) In this case, it should generate also an Exchange Gain for 244 UYU, based on the amounts above:

    a) Adjustment (61*28.2213) = 1721.5 UYU

    b) Invoice (61*24.2213) = 1477.5 UYU

    c) Exchange Gain = 1721.5 UYU(a) - 1477.5 UYU(b) => 244 UYU

I didn't find any SLA event for adjustments that generates the Exchange Gain/Loss.

Is there any process that must be run to generate the Exchange Gain/Loss journals, or do I need to customize the SLA Adjustment to generate the journal entries?